Nestle into a human-sized bird’s nest or stretch out on a suspended web 50 feet above the forest floor at the Morris Arboretum Tree Adventure in Philadelphia, a journey through the treetops punctuated with lookouts, a swaying bridge and fun play areas for children. The ‘Out on a Limb’ portion of the Tree Adventure consists of a 450-foot walkway made of steel and cedar wood, and illuminated with LED lighting.
Designed by Metcalfe Architecture & Design and winner of a number of awards including the 2010 American Association of Museums Excellence in Exhibition Design Award, Out on a Limb is both fun and educational, employing a “play-to-learn” strategy that aims to foster respect for nature in children.
The structure, which was pre-fabricated offsite, is made from recyclable metal and sustainably harvested, 100-percent renewable Western Red Cedar. Naturally bug- and rot-resistant locust wood decking will ensure that the Boardwalk stays safe and beautiful for a long time. Very much a part of the woods in which it is located, the structure is nevertheless entirely free-standing. Placed on small foundations called “micro-piles”, the boardwalk was engineered to put the least amount of strain possible on the root systems of the trees.
“We spend our whole lives on the ground looking up,” said Paul Meyer, director of the Morris Arboretum. “But I think there is something instinctively attractive in the trees. Why else would we want to build tree houses as children? Something like this allows us to escape the bounds of the earth.”



