Constructing the green wedge in the planning discourse - a case study of Central Park in Helsinki, Finland

ABSTRACT This article explores the construction of the green wedge in the planning discourse in Helsinki’s Central Park over three phases: its establishment in the early twentieth century, the first statutory plan of the 1970s and in the present context. Often described in quantitative methods emphasising physical and spatial qualities, the study instead examines the conceptual and historical dimensions of the park. The thematic analysis of the planning discourse looks at four principles characteristic of the green wedge model— the relationship between the park and the city; the continuity and connection from the centre to the outskirts; recreation and health; and nature as beauty and biodiversity. With the focus on the consistencies and changes, this study highlights the resilience of this over 100-year-old green wedge and demonstrates that Central Park has been able to accommodate new needs and functions while sustaining most of its original aims.


Introduction
The idea of green wedges-continuous green spaces from the city centre to the outskirts-is an established planning principle which goes back to the late nineteenth-century and early twentiethcentury park systems thinking. Frederick Law Olmsted's park systems in the US and the 1910 star model for Greater Berlin were its well-known applications which received followers in many cities, such as London, Melbourne, Rome, as well as Helsinki, the case study of this article (see, e.g., Dümpelmann, 2009;Lemes de Oliveira, 2017). The green wedge principle is closely linked to the planning models of urban nature and to the ideas about the functions of urban greenery and the benefits it produces as well as the prerequisites for a healthy urban life. Although altered in many ways, green wedges have maintained their central role and proved to be a viable principle in strategic green space planning (Lemes de Oliveira, 2017, pp. 217-227;Sturzaker & Mell, 2016, pp. 162-166).
Despite the key role of green wedges, they have received limited attention in research. Instead, researchers have tended to concentrate on the green belt model (e.g., Amati & Taylor, 2010;Evans & Freestone, 2010;Sturzaker & Mell, 2016). The most extensive study on green wedges is Lemes de Oliveira's Green Wedge Urbanism (2017), which was the first comprehensive review of the history of green wedges and their current applications. Moreover, Dümpelmann (2009) has studied the history of park systems and the transatlantic transfer of ideas between the US and Europe. European planners were particularly inspired by the works by Frederick Law Olmsted. Olmsted and especially the Emerald Necklace have received attention by, for example, Zaitzevsky (1982) and Birge-Liberman extending from the city centre to Helsinki's north border (City of Helsinki, 2018, pp. 12, 22) (Figure 1) Although the area is called a park, it largely consists of forest, except for the culture park in the city centre, the sports and exercise areas in the middle and the fields in the north. During its more than 100 years of history, Central Park has adapted to the needs of the growing city. The planning principles adopted for the protection of the park have become established in urban planning.

Aims, materials and methods
Although Central Park is the city's most important green space, it has received limited attention in research. Despite its status as the first green wedge, it has hardly been noted as a historic green space: this is evident, for example, in its management plan (2018) which focuses on the ecological values of forest areas and the social values and the use of the park. Thus, this study examines the historical and conceptual dimensions of Central Park in the planning discourse from its establishment phase of the 1910s to the present planning phase. It pursues the idea that places represent not only a geographic location and a material form, but also an investment with meaning and value-places are constructed, narrated, perceived and imagined (Gieryn, 2000, pp. 464-465).
This article examines the construction of the green wedge by looking at the narratives and ideas of which some have endured and some changed over time. How has the green wedge and its materialisation in Central Park been conceived and what functions and values have been assigned to it? Has it remained constant, or has it been modified and accommodated with new aspirations and objectives? The study addresses Helsinki, but it contributes to a broader understanding of green wedge planning and a model that has for over a century envisaged a closer relationship between city and nature.
This study looks at the planning discourses at three phases: during its establishment in the 1910s, in the 1970s' master planning phase, which was the first statutory plan for the park, and at the present context of the densifying city, which has challenged the position of the park. By selecting these three key planning phases, the aim is not to provide a comprehensive review of the development of the park but to build a cross-section for analysing the narratives of Central Park. The research data consists of primary sources and planning documents from each planning phase. Early planning documents include ample writing and plans by Bertel Jung, the creator of Central Park and the first town planning architect of Helsinki. The next planning phase encompasses the first statutory master plan of 1978, including its extensive written report. In the Finnish planning system, the plan is called component master plan, meaning the master plan for separate subareas. The final phase comprises the 2018 Nature and Landscape Management Plan Draft and the 2016 Green Network Development Plan, in addition to newspaper discussion related to planning of Central Park.
The empirical basis of the study is a qualitative content analysis of the planning discourse, acknowledging that the basis of green space planning is social and linguistic in nature. Discourse is defined, according to Hajer (1995, p. 44), as 'an ensemble of ideas, concepts and categories through which meaning is given to social and physical phenomena, and which is produced and reproduced through an identifiable set of practices'. The analysis of the planning discourse searches for meanings and central themes in the texts and organises the data in a compact and clear manner. The planning phases are analysed through a thematic framework, consisting of the key principles of the green wedge, formulated on the basis of Mawson (1911) and Lemes de Oliveira (2017). Within the thematic framework, the narratives of the planning phases can be analysed systematically, with the focus on the repetition and contrasts-consistencies and changes-in the planning discourse.
The structure of the article is as follows: in the next section, the origins of the green wedge and its key principles are described, providing a framework for the thematic analysis. The following two sections present the case study of Central Park, starting with the context of the planning phases. The thematic analysis is then presented, based on the framework and organised according to the three planning phases. The last section consists of the discussion and the conclusions of the study.

The origins of the green wedge
The radial green wedge is a transnational idea, which took root at the turn of the nineteenth and twentieth centuries in both Europe and America and spread widely through books and urban planning exhibitions and through urban planners' journeys and mutual correspondence (Dümpelmann, 2009;Freestone, 2015;Herman, 2014). The green wedge model was imbued with the park systems thinking, established in Northern America and pioneered by Frederick Law Olmsted. The significance of urban parks was raised onto a higher level: whilst the earlier park planning aimed at a green oasis in the midst of buildings, the park systems emerged as a potential for the entire city and the society (Sutcliffe 1981, p. 197). For example, one of the most influential works is Olmsted's Emerald Necklace in Boston (1878), whose parks, parkways and waterways form a coherent network connected to a wider regional green space system (Zaitzevsky, 1982, pp. 81-94).
The park systems thinking coincided with the urban planning reform and merged with the garden city thinking (e.g., Dümpelmann, 2009). Camillo Sitte separated two functions for urban greenery: ornamental and sanitary (Collins & Crasemann Collins, 1986, p. 319). The importance of ornamental urban greenery on squares and streets was above all psychological, whilst the expansive parks of sanitary urban greenery offered protection from dust, noise, wind and heat. Sanitary urban greenery laid the ground for modern urban planning, and it was manifested in numerous applications, such as the green belt surrounding Ebenezer Howard's) garden city model.
The park systems idea was also connected to the city's growth models. One of the most influential examples was the winner of the third prize for the Greater Berlin urban planning competition by Bruno Möhring, Rudolf Eberstadt and Richard Petersen, showcased in Berlin's urban planning exhibition in 1910 (Borsi, 2015, p. 50;Sutcliffe 1981, p. 198). The plan compared two different models: firstly, the city's concentric model with the green belt surrounding the city and secondly, the radial star city which introduced radial green wedges and corridors for urban growth. The radial model made an impact on numerous urban planners and established a basis for the adaptation of the green wedge in many cities, including in Helsinki. The model was considered to facilitate the growth of the city better than the concentric model with the green belt (Mawson, 1911, pp. 83-84;Jung, 1911a, pp. 95-98). Mawson (1911 , p. 79) described park systems as a chain of parks, gardens and open spaces 'arranged according to a comprehensive plan, and extending from the city into the open country, the object being to secure a continuous through route under leafy canopies, or across beautiful green lawns or naturally wild common reservations'. This description emphasises the comprehensive planning approach, continuity, diversity and the connection from the city to the countryside. Mawson (1911, p. 84) regarded the radial parkways as 'the soundest and most in harmony with town growth and expansion'. He saw two prime objectives for the park systems. First, they served for recreation, bringing 'continuous open areas, with their accompaniment of greenery, flowers and ornamental water, within easy reach of the population' (p. 85). Second, park systems were the lungs of the city, ensuring hygiene, healthy conditions and fresh air (1911, pp. 79, 86).

The principles of the green wedge
Mawson's principles provide an interesting starting point for the thematic analysis of Central Park. They also correspond to the characteristics, defined by Lemes de Oliveira, for future application of green wedges. He emphasises the balanced relationship between built-up areas and green wedges, the connection between the city and the countryside, the continuity of the green wedges, public access and use, the integration of ecosystem services and the systemic integration into a comprehensive plan (Lemes de Oliveira, 2017, p. 220). Based on these general principles, a framework for the analysis of Central Park was produced, in order to reveal the key narratives of the planning discourse. The framework consists of four topics: 1) the relationship between the park and the city, also including the comprehensive planning approach, 2) continuity and the connection from the centre to the outskirts, 3) recreation and health for the residents and 4) nature as beauty and biodiversity, referring to the different roles of nature in the city.

Central Park of Helsinki and its three planning phases
The planning discourse of Central Park is analysed in three planning phases, starting from the establishment of the park and ending with the current state. The timespan of the study covers more than a hundred years and evinces the urban growth and development of the city of Helsinki (Figure 2). In the early twentieth century, population growth, industrialisation and changes in economic structures challenged urban planners to develop new kinds of solutions to meet the needs of fast-growing Helsinki. Bertel Jung, the first town planning architect to take on the post in 1908, held a key position in the task. Jung, along with many other architects, had become familiar with the American park systems and Berlin's radial city and the green wedge presented in the 1910 urban planning exhibition (Jung, 1911a, p. 95;1911b, p. 137). Park systems and coherent green areas corresponded with Jung's social reformist goals and the aims to improve the living conditions of the working classes. According to him, the wedge-model was better suited to the growth of Helsinki located on a peninsula than the traditional green belt model, which would restrict a city's growth and have an adverse effect on the transport system and land policy (Jung, 1911a, pp. 95, 98).
Jung published his first plan for Helsinki's Central Park in the Arkitekten magazine in 1911 ( Figure 3) and defined it further over the next few years. The plan was approved in 1914 by the City Treasury and the Public Works Board, which reserved the areas appointed in the plans for Central Park (Jung, 1914). The park and forest zone started at the heart of the centre by Töölönlahti bay and continued to the edge of the city along the Vantaanjoki River. The basis for the park and the forest zone was that the land was owned by the city-either existing parks or new land acquisitions that could be reserved for Central Park (Jung, 1914, p. 9;Yrjänä, 2013, pp. 43, 51). The extent of the park zone was 600 hectares, equivalent to 15 m 2 per inhabitant (Jung, 1916, p. 149). The plan also included a proposal on the growth of the city and land use as well as the most important rail connections. Jung integrated parks into urban planning and started planning housing, transport and the green network as a whole. The change was significant because park  (Jung, 1911b, p. 139). The author has added the colour green to emphasise the planned park.
planning had before this focused on individual green areas under the responsibility of the park service and the city gardener.
Park planning of the 1910s created the basis for the outlines of Helsinki's green space network and its legacy has carried far. Birger Brunila, who worked as the town planning architect after Jung from 1917 to 1948, continued the visionary green space planning. Central Park was expanded with new land purchases to the north and new green zones were developed (Brunila, 1962, p. 73). During the twentieth century, Central Park established its position as the most central green space of the city. However, its status was not secured with official planning mechanisms. The park's boundaries were confirmed for the first time only in the component master plan of 1978 (Figure 4) when the park was threatened by the growth of the city (City of Helsinki, 1975, p. 30). The population of the city had more than quadrupled since the establishment phase: in the 1910s, the population was 118,700 and in the mid-1970s 503,000 (City of Helsinki, 2019, p. 27). The component master plan, influenced by the strengthening environmental planning movement, aimed to respond to the increasing use and the construction projects which threatened the park (City of Helsinki, 1975, pp. 30-31).
The last planning stage of Central Park in the 2010s also connects to a phase of urban growth when the values of the park were regarded to be under threat. Urban densification, which started in Helsinki in the 2000s, was the main objective of the comprehensive plan of 2016, which followed the international compact city thinking and prepared to increase the population of Helsinki from 628,000 in 2016 to 890,000 by 2050 (City of Helsinki, 2016, pp. 66, 170). Although the principle that the size of Central Park would not be reduced was confirmed in 2006 (City of Helsinki, 2006), the comprehensive plan of 2016 attacked that by identifying sites for construction in Central Park along with many other green spaces. The aim of the 2016 Green Network Development Plan was to respond to the pressure of densification. It presented guidelines for strategic planning of the green structure network, including Central Park, which was recognised as one of the key elements of the network (Jaakkola et al., 2016, pp. 5, 38-43) (Figure 5) The nature and landscape management plan, drafted in 2018, presented more detailed objectives and implementation measures for different areas of the park. It was based on thorough surveys on user experiences and nature values, aiming to reconcile the use and biodiversity values, which had increasingly gained importance since the 2010s (City of Helsinki, 2018, pp. 31-32).

Relationship between the park and the city
First phase. The important premise for Central Park was the idea of parks as an integral and essential part of a city and urban planning. The forest and park zone by Jung was prompted by the urban planning reform aiming to improve the quality of urban life. It derived from the antiurban ideal of the nineteenth century, suggesting an escape from the evils of the city (Cranz, 1982, p. 5;Duvall et al., 2018, pp. 482-483). It also corresponded to the concern for the decrease in green spaces in the growing city (Jung, 1911a, p. 99).
However, the Central Park plan was more than just a declaration emphasising the need for parks; it was Helsinki's first overall land use plan and simultaneously also the first proposal in Finland resembling a comprehensive plan (Salokorpi, 1984, p. 274). It epitomised the turning point in urban planning and the linking of green space planning into the field of city planning, expressing the aspiration to find a balance between urban growth and nature.
Second phase. As environmental planning gained importance, natural resources and green spaces were brought to the agenda of comprehensive planning (e.g., Daniels, 2009, pp. 183-185;Hautamäki, 2016, p. 187). In the 1970s, several strategic green space plans were drafted, the component master plan of Central Park being among the most significant ones. Despite its status as Helsinki's most important recreational area, Central Park did not have the protection provided by a city plan. The apprehension over the preservation of the park initiated the component master plan  1978, which confirmed its status and boundaries. The city had become a threat to the park, which was evident in the various construction and road projects as well as in air pollution and the soil erosion of the park (City of Helsinki, 1975, p. 30). Tackling and reducing the damages was one of the most important objectives of the plan: new road plans across the park were annulled; construction was aimed to be centralised, and the park's boundaries were verified (City of Helsinki, 1975, pp. 11-12, 43).
Third phase. The 2016 comprehensive plan and its densification objectives challenged the integrity of Central Park and its binding boundaries. The plan proposed major construction at the edges of the middle part of the park, the park's northern fields and in the vicinity of the park (City of Helsinki, 2018, p. 9). The construction plan launched a prominent citizen movement and a protest for the protection of the park. The plan for the middle part was annulled by the supreme administrative court, which judged it as contrary to the regional land use plan and its stipulation for a recreational area (Supreme Administrative Court, 2018, pp. 22-23). The case clearly demonstrates that the polarisation between urban development and Central Park-and green structure in general-has increased (Hautamäki, 2019). The original idea of the green wedge to balance urban growth and nature has been complemented with the narrative of protecting the park against the city.

Continuity and the connection from the centre to the outskirts
First phase. According to Jung, the forest and park zone was to be uniform and extend from the centre of the city to the outskirts 'to the vacant fields and rustling forests of the country' (Jung 1918, p. 18). According to the initial green wedge idea, the connection with the country and the city was emphasised as the wedge would funnel air, sunlight and greenery from the countryside into the urban fabric (Lemes de Oliveira, 2014, p. 357). Another important characteristic was accessibility: parks had to be within easy reach from all city districts and particularly for the more deprived residents (Jung, 1914, p. 8).
Second phase. Ensuring the integrity of the park by confirming its boundaries was the starting point for the component master plan 1978. Similar to Jung's era, the plan stressed the continuity from the city centre to the outskirts. Moreover, it had a specific emphasis on the connections of Central Park to the broader green structure network (City of Helsinki, 1975, p. 30). Construction and the barrier effect of the road networks were regarded as the core threats for continuity; new road reservations were proposed to be removed and simultaneously the existing recreational routes were purposefully developed (City of Helsinki, 1975, pp. 30, 40).
Third phase. The development plan 2016 continued the narrative of continuity and stated that Central Park is 'the wooded spine from the dense urban centre to the wilderness' (Jaakkola et al., 2016, p. 39). The plan emphasised the transition from the urban park in the south to more natural areas in the north. The network was introduced as a new dimension to the concept of continuity-all parks were to be conceived as part of a network of open spaces linked together (Cranz & Boland, 2004, p. 104;Jaakkola et al., 2016). This vision emphasises in particular the ecological connectivity and the significance of the forest network to biodiversity which had gained importance in city planning in the 2010s (City of Helsinki, 2018, p. 16).

Recreation and health for the residents
First phase. Central Park's core aim-recreation-has remained constant but also obtained new recreational functions and target groups. Jung defined three cornerstones to recreation: experiencing nature, activities and health aspects (Jung, 1911b, p. 138). This vision was typical in the early twentieth century during which reform parks were about to replace picturesque landscape parks (Cranz, 1982, p. 61). Reform was also the premise for Jung, who aimed to improve the recreational opportunities of the city's residents and particularly the lower classes and to alleviate the disadvantages of the city. Urban green spaces also served hygienic purposes: extensive parks, located close to housing, worked as vessels of clean air (Jung, 1914, pp. 7-8;Cranz, 1982, pp. 5-7). The concept of hygiene was also linked to social hygiene and the idea of the dangers threatening the lower classes, such as alcoholism and tuberculosis, which were considered to be the consequence of cramped and unhygienic living conditions (Harjula, 2007, p. 36). The reform implied an educational aspect: parks were places for moral and intellectual reform providing opportunities for learning socially appropriate manners and skills (Ward Thompson, 1998, p. 18).
Second phase. Whereas Jung and the reform era advocated the park facilities for the deprived classes, the 1970s stressed recreation for all residents (Cranz, 1982, pp. 230-231). The hygiene aspect was disregarded in the 1970s planning discourse. However, the plan still applied the metaphor of parks as the lungs of the city and emphasised health aspects-the capacity of Central Park's forests for clean air and preserving the oxygen balance (City of Helsinki, 1975, p. 31). The main attention was turned to recreational facilities; Central Park was considered, above-all, as a leisure time place for urban-dwellers. Based on studies, there were more than 2 million visits per year to the park in 1970, and the most popular usages were walking, jogging and skiing (City of Helsinki, 1975, pp. 20-21, 31). Shorter working weeks and increased leisure time created a gap which generated a demand for recreational services (Cranz, 1982, p. 62). The aim was to expand the recreational network and to build services requested by users: cooking shelters, benches, toilets, hiking lodges and kiosks (City of Helsinki, 1975, pp. 36, 38).
Third phase. Central Park's current development is a consistent continuation from the 1970s' approach with the focus on facilities and activities (City of Helsinki, 2018, p. 22). Programmed recreation with different recreational facilities has been taken even further, and the entire park area is presented as a network of facilities (Jaakkola et al., 2016, p. 42). The planning stresses exercise and everyday activity, which have been defined as a priority in the strategy of the city (City of Helsinki, 2018, p. 31). The restorative benefits of nature, which were bypassed in the 1970s, have returned to the planning discourse on a fairly similar approach to the 1910s. Outdoor recreation in wooded surroundings and experiencing calmness and nature support relaxation and stress release (City of Helsinki, 2018, p. 12;Jaakkola et al., 2016, p. 43).

Nature as beauty and biodiversity
First phase. Bringing nature to the city has remained the park's key objective. However, the notions of nature have changed. In Jung's discourse, nature came up as a source of recuperation and beauty. Nature was associated with the countryside and its aesthetic and hygienic virtues and as the remedy for the nuisances of the city (Duvall et al., 2018, p. 483). Central Park 'represented nature to the exhausted masses who had forever been cut off from it by the city walls' (Jung, 1914, p. 7). Although Jung proposed an intensively built and formal urban park in southern Central Park, wilderness played the main role elsewhere. Beauty appeared as a nature park, as beautiful lookouts and carefully maintained tree stock, 'as a piece of Finnish nature at the heart of the capital' (Jung, 1914, pp. 12-13).
Second phase. The notion of nature of the 1970s differed greatly from the earlier idealisation of natural beauty as the human-centric perspective on nature as an amenity was complemented with ecological frames (Duvall et al., 2018, p. 492). In the 1970s, Central Park was regarded above all as a nature-like recreational forest, which emphasised biological, ecological and landscape visions. Constructed urban parks were regarded as the opposite of nature, and it was declared that the recreational forest must not be changed into a park-like landscape (City of Helsinki, 1975, pp. 34-36). However, scenic values were also appreciated: for example, diverse spaces and open landscapes supported the legibility of the area (City of Helsinki, 1975, pp. 14, 28). The component master plan aimed to preserve vegetation and landscapes and assigned several nature and landscape sites for protection. In accordance with the growing environmental movement, nature was considered to be under threat, and in need of protection. The denial of the value of urban nature, its neglected role in the plans, the gradual decay of the area, its use as construction reserve as well as the failure to renew the forest were recognised as problems in Central Park (City of Helsinki, 1975, pp. 12, 33, 31).
Third phase. Whilst the component master plan of the 1970s only proposed protection, there are currently already six nature reserve areas (HS 23.11.2019;City of Helsinki, 2018, p. 14). In addition, the discussion on nature has changed. The expression 'nature-like' has been replaced with 'natural state', biodiversity and ecosystem services as a response for growing environmental concerns-climate change mitigation and the loss of biodiversity. According to the city strategy, the aim is to increase biodiversity by preserving valuable forests in their natural state and leaving decaying wood in suitable places (City of Helsinki, 2018, pp. 31-32). There has been a steep increase in it of forests kept in their natural state: in 1998-2007 the percentage was 12% whilst now it is as high as 41%. Biodiversity also pertains to network thinking: Central Park's extensive and coherent nature area has a key role as part of an ecologically significant forest network, which provides an important connection for movement and a resting place for wildlife, such as the flying squirrel (City of Helsinki, 2018, pp. 16-17, 35-36).
Although promoting biodiversity has been approved at a high political level of the city's strategy, there is no consensus on how this should be implemented in practice. A reflection of this is that the nature management plan was unanimously dismissed by the political committee in autumn 2018. Politicians and Central Park activists strongly criticised excessive felling and the 'old-fashioned idea that Central Park would need to be overly managed' (YLE 13.11.2018). Respectively, according to the civil servants who had produced the plan, the aim was to ensure the sufficient regeneration of forests, safety and the accessibility of routes by felling dangerous or dead trees and by thinning saplings (HS 12.11.2018;HS 13.11.2018). However, the interpretation of the appropriate forest management differed on a political level and a decision was made to proceed with controlled unmanagement which ' . . . will mean a little more decaying wood than has been allowed in the past' (HS 13.11.2018). The dispute over what a forest should look like and what kind of urban nature is acceptable is a sign of the politicisation of urban nature. Forest management, which has in the past been the responsibility of the civil service, is now under tight political guidance.
The notion of nature also pertains to scenic values although natural beauty is no longer in the forefront (City of Helsinki, 2018, pp. 38-39). Since the 1990s, the growing awareness of cultural environments has highlighted cultivated cultural landscapes along the Vantaanjoki River which have been accepted as a nationally valuable landscape area (City of Helsinki, 2018, pp. 10, 17-18).

Discussion and conclusions
Studying the planning narratives of Central Park reveals interesting differences between the planning phases. The park evinces the continuous negotiation between the city and nature, elucidating the planning principles and perceptions attached to urban nature. The most significant difference between the three planning phases concerns the concept of nature. The notion of nature, which initially stressed natural beauty, first changed to the ecological and nature-like perspective and finally to the defence of the natural state and biodiversity, which is also reflected in the establishment of nature reserve areas and the new aesthetics for urban nature.
A clear difference between the planning phases also concerns the relationship between nature and the city. The original idea of the green wedge to balance urban growth and nature has been complemented with the narrative of protecting the park against the city. The recreational meaning has sustained, but its character has changed. The initial idea of providing revitalising natural environments to the deprived classes shifted to a debate about leisure time and programmed recreational services for all. The debate on social hygiene to mitigate the city's problems has changed to a discussion about restorative natural environments and the health impact of exercise.
Studying the planning discourse of Central Park also demonstrates the durability of the green wedge idea and its key principles. One consistent principle involves the park as an integral part of a city, which has been strengthened with a variety of metaphors from the lungs of the city to the forest spine. A mutual characteristic is also to consider the park as part of comprehensive planning. Moreover, the park has been defended at different stages with remarkably similar arguments: on the one hand, with the positive effects of urban nature and on the other, with the city threatening the park and the reduction of green spaces.
The park's important characteristics have also been interpreted in similar terms, although the rhetoric may have slightly differed. Coherence, continuity and accessibility have been important at all stages, although since the 2000s the connectivity has focused on the ecological network. The green wedge's connection from the centre to the outskirts has persisted, emphasising the transition from the urban park in the south to more natural areas in the north. Moreover, scenic values have been appreciated in each planning phase, with slightly different nuances, emphasising either beauty, the diversity of landscapes or the uniqueness of cultural landscapes.
Central Park of Helsinki, as the first Finnish application of a green wedge, has managed to adapt to the requirements of the growing city during its 100-year history. It has kept its place as a key green space in the city and fulfilled various needs: recreation, health and nature conservation. It has created a frame for the green network and launched the strategic planning of green spaces with a close link to urban planning. The park has been established as a metaphor and a planning principle which have become institutionalised. Central Park is about resilience-sustainable ideas about urban nature and the ability to respond to changing circumstances and needs.