Since Holland is mostly under sea level, keeping houses from flooding is a constant problem. This concept fixes that problem by just having an apartment complex that floats.

The Citadel is the residential part of the "New Water" complex, which tries to embrace Holland's waterworld-ness instead of fighting it. It'll have a floating road to the mainland as well as plenty of boat docks for its 60 units. Apparently it'll also be 25% more energy-efficient than an equivalent complex on land by using the surrounding water for cooling. It looks kind of crazy, but the sort of crazy that could actually work. [Inhabitat]