Until a few years ago, it used to be dumped in landfills, but it is tricky to find much space on an island where more than 70% of the land is covered by mountains.

BBC: Technology

If the home is connected to land by a 180-foot-long bridge, is it still considered an island?

FORBES: Private Islands For Sale - Luxury Digs Included

When land is scarce and expensive you build close and high, and Manhattan is an island of solid street walls and shoulder-to-shoulder skyscrapers.

WSJ: The Greatest Grid | Museum of the City of New York | Crosshatching a Miracle | By Ada Louise Huxtable