23. October 2015

Aventura – Europe’s longest playground structure

It begins in a shaky fashion at the foot of Bromberg Hill. A large access net leads up to a treehouse-like tower. And this is just the beginning – the beginning of Europe’s longest climbing structure. Meandering 168 metres up the hill are a great variety of tunnels and bridges, balancing elements and rubber mats, which pass through multiple towers along the way.

Planning

“Aventura – Play Mountain” is located in Medebach, a small town and holiday resort in Hochsauerland, which attracts hikers in summer and skiers in winter. After a building phase that was completed in record time, the facility was officially opened at the end of September 2015, having already been given TÜV certification the previous month. The new “playground” is located on land provided by the town of Medebach and forms part of Center Parc, a family resort surrounded by nature. The facility can be used for free by resort guests, visitors to the region and local inhabitants alike. The idea for the construction of a large, recreational facility that was also required in some way to be the only one of its kind in Germany goes back a few years. In 2007, winter storm Kyrill left severe damage in its wake. It was Center Parc’s landscape architect and biologist, Jean Henkens who originally came up with the idea, drawing inspiration from Bromberg being known in history as “where the wind lives”. This led to the choice of air, one of the four elements, to be the underlying theme for the giant climbing structure.
The project was then further developed and implemented by the Paderborn based landscape architectural practice Gasse|Schumacher|Schramm in cooperation with Berliner Seilfabrik.

Implementation

“What makes the project unusual is its scale,” explains Marius Kotte, architect and head of the construction and development department at Berliner Seilfabrik. “Above all, we needed to pay the utmost attention to project management, since the project involved a great degree of planning and development as well as the preparation and implementation of various production processes. The challenge lay in our delivering this major order whilst not neglecting our other clients and their orders.” The project was sub-divided into nine segments, the manufacture of each segment being treated as an individual contract. Structuring the project in this way ensured its completion on schedule. Rising to the challenge of new product development during the construction process proved particularly successful. A number of innovations have been incorporated into Play Mountain: several towers are being seen for the first time, as are the connections between the segments and their connective elements, e.g. between tubes and joints. Although the tallest tower is 7.8 metres high, at no point is it possible to fall any further than the legally-permitted distance of three metres.

Nets inside lead the visitor to a long, spiralling tunnel slide. Another tower is distinguished by a special feature: by lying on a viewing net, visitors can marvel at the wonderful surrounding landscape. These towers are clad in bamboo panels. Berliner Seilfabrik selected bamboo not only because it is more durable than wood, but because it makes a smaller environmental footprint. Being a grass species, after harvesting bamboo can grow again, unlike wood.

Suspended between the posts inside two towers are large cocoon-like spheres, access to these being via plate-shaped nets. It was important for these elements to be as transparent as possible while still remaining safe. With this in mind, they were enclosed in a safety net of fine mesh. Such netting was also employed where a small gully is traversed by the climbing structure, at which point a classic suspension bridge is used to cross above a cliff face. Approximately 2000 metres of bright red rope has been used for the 22 connecting elements of the structure. As well as the ever-popular net tunnels and classic suspension bridges, new transitional elements can also be seen, such as the liana bridge, a narrow net walkway suspended from long ropes, not to mention a tunnel enclosed in a rubber membrane. One segment—involving a combination of sloping and balancing—is particularly challenging. It is here that the far from fully grown visitors prove to have a distinct advantage. Also popular is the so-called chessboard bridge, comprising squares of rubber stretched between holding ropes. Here, the children can hop, sway and relax.

Foundations and Impact Protection

Close to thirty six tons of steel was delivered to the building site. Almost one hundred posts were used, the heaviest of which, at 10.4 metres long, weighed 450kg. Test drilling prior to the building phase on the upper reaches of the hill in November 2014 encountered solid rock near the surface. However, while excavating the foundations in June 2015, this rock turned out to be soft shale. The foundations for the posts had to be adjusted accordingly.
On the ground beneath the towers and platforms, the steep gradients were levelled off so as to prevent the impact protection material from being washed away by rain. In some areas wood chips were chosen for impact protection, while in others, turf was selected. The colours of both these blend in with nature while also ensuring the highest safety standards. Over time the lawn areas will change into flower meadows without compromising their impact protection properties.
The gradient of the slope is approximately 21 per cent, but can vary dramatically, at some places reaching as much as 46 per cent. The technical solutions devised by Berliner Seilfabrik allow for small modifications to be carried out to the structure on site. For example, the height of the so-called T joints, which fix rope, chains and tubing to the posts, are adjustable. This allows for any minor revisions to the plan deemed necessary in situ due to vagaries of the terrain.

For Small and Not-so-small Users Alike

Climbing to the top of the structure is not easy. But those who perhaps don’t as yet dare to go through the towers or cross the bridges can play to their heart’s content at the lower end of the facility in an area specially designed for small children. Here they are welcomed by two large nest-swings and “Trii”, a small tree house with a slide. For accompanying adults, a paved path runs parallel to the entire climbing structure.