The next boom town isn't really a town at all, but an island. Though too small to be considered a city, Hashima Island off western Japan was at one point in history the most densely populated place on the planet [source: Burke-Gaffney].
In 1850, the historically closed-off country opened itself to increased trade with the world. At this time, the expansion of steam technology gave rise to the popularity of coal as fuel. The Fukahori family drilled the first successful coal shaft on Hashima in 1885. Three years later, the Mitsubishi Corporation purchased the mine.
By 1907, additional land had been reclaimed and high sea walls built. The result was an island that looked more like a ship. A local newspaper reporter gave it the nickname gunkanjima, the Japanese word for battleship.
In the early 1900s, Hashima produced 150,000 tons of coal annually. By 1941, it peaked at 410,000 tons [source: Burke-Gaffney].
The island boasted its own microcosm: Schools, a gym, a movie theater, bars, restaurants, temples and more were crammed onto Hashima's 15 acres. In 1959, the island was home to 5,259 people [source: Burke-Gaffney].
But as we've seen so far, boom towns eventually bust. Coal was king in Japan until the late 1960s, when petroleum took its place as a source of energy. Coal mines across the country were shuttered, and on April 20, 1974, the last residents departed Hashima. Today, dilapidated concrete high-rises are all that's left.
In contrast to the planned exit of Hashima, no one expected what would happen in our next boom town to go bust.