Peleliu is important because of its airstrip, a hard-surfaced field capable of launching long-range fighter-bombers. The island is just six miles long and two miles wide, but the terrain is exceptionally rugged, a film of thin soil laid atop coral and limestone. A thousand yards off the beach rise the jungle-covered Umurbrogol ridges, a series of low, jagged peaks forming the island’s spine. [Source: "Killing the Rising Sun: How America Vanquished World War II Japan"]