The platform through the tree canopy will be 4 stories high. It takes a very large crane and some brave construction workers to get it all in place.
The workers started laying the wood platform down on top of the steel structure. The final Canopy Walk will look completely natural and fit into the surroundings of the Arboretum.
Building "The Bird's Nest" while still on the ground. It will eventually take its place up in the trees, as a central part of the Out On A Limb exhibit.