Located in a valley in the province of Makkh in western Saudi Arabia, is the small city of Mina, also known as "the city of tents". There are more than 100,000 air-conditioned white tents, arranged in neat rows, covering every available open space in the valley, according to Amusing Planet. Every year, millions of Haji pilgrims gather in the tents of Mina, which is only about five miles from the Holy city of Mecca, for one of Islam’s holiest rituals. It is in Mina that, on the third day of Haji, the pilgrims perform the ritual stoning of the Devil by pelting stones at pillars in Mina, reports the Daily Star. The tent city is mostly deserted during the rest of the year.

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According to Amusing Planet, pilgrims used to bring their own tents to Mina. In the 1990s, the Saudi government installed permanent cotton tents but afire broke out in 1997, killing over 300 people and destroying 70,000 tents, reports The New York Times. After this disaster, the city was rebuilt with a heat sensitive sprinkler system andfireproof, fiberglass tents coated with Teflon.