Navassa, an American island filled with bird poop between Jamaica and Haiti.
Lost States contains colorful stories of territories, islands, and countries that failed to become U.S. states. The most fascinating are the guano islands.
Guano, or bird shit, was used in the 19th century to make fertilizer and explosives. The U.S. Congress passed the Guano Islands Act in 1856. It allowed Americans to take possession of any island containing guano, so long as it's not occupied and not within the jurisdiction of other governments.
Over 100 islands were claimed under the Act. Today, only about a dozen remain American. Navassa Island, above, is administered by the U.S. Fish and Wildlife Service.
Midway, Johnson, Kingman, Palmyra, Jarvis, Howland, and Baker were all acquired through the Bird Poop Islands Act of 1856.