The wonderful instructables has this great make
Come and see this bridge in Petersburg, Alaska!
I acquired a grant to put in a bridge over a stream that was between a park and a mile long trail. The plan had been to install a glue-lam or log bridge across a 50 foot wide part of the stream. Building a log bridge is actually pretty easy if you have big timber to work with. But a citizen approached me and asked if he could design and guide the construction of a cantilever bridge with a small hut on it.
This design incorporates a “sod” roof of locally harvested mosses as well as integrated benches. The entire structure except the plywood on the roof is constructed of red cedar. Most of the pieces were fabricated in a wood shop and then carried out and installed.