The idea is to get from one tree to another using cables, pulleys, and the like. In case you wonder, people are really doing this for fun. It ain't easy though, and you feel some muscles protesting against the sudden action :-)

It may sometimes look easy, but losing your balance is easy too! :)

The last picture really shows how difficult it was (well that's just the flash bouncing of the mist, but who cares :)

In case you still want to try this yourself, there are a couple of parks in France. See the Aventure Parc web site for more information: http://www.aventure-parc.fr

It really is fun (and hard work) :-)