This is an old revision of the document!
Two towers were built. The bases are 4' by 4' wide. The towers have two floors, with a central ladder to climb between them. The ground floor is at 1' high, and the top floor is at 6' high. Three sides of the ground floor are enclosed by a truss-like structure. The top handrail is continuous apart from one side, which has a half length handrail to allow walking from one tower to another (or onto a piece of 6' deck).
The towers were built as a left and right symmetrical pair. All parts were designed to be interchangeable, allowing for almost any configuration, but due to various inaccuracies of planning and construction the parts don't all line up. A suggested design for assembling follows - deviate from this at your own risk!