The Cave of Swallows, also called Cave of the Swallows (Spanish: Sótano de las Golondrinas), is a pit cave situated in San Luis Potosí, Mexico. The entrance lies along a sloped section of karst, is elliptical in shape, and measures approximately 160 by 205 feet (49 by 62 m). The entrance is undercut around its entire perimeter, and the pit opens up to a room that measures approximately 995 by 440 feet (303 by 134 m). The low point of the entrance provides a 1,094-foot (333 m) freefall drop to the bottom of the cave while the high point provides a 1,220-foot (370 m) freefall drop. These measures make it the largest cave shaft in the world, second deepest pit in Mexico and the 11th deepest in the world.