Los Angeles may be right next to the Pacific Ocean, but there's also a hidden sea of swimming pools that dot its urban sprawl. Those 43,123 pools have been painstakingly chronicled in a new research volume dubbed the Big Atlas of LA Pools, which was put together by cartographer Joseph K. Lee and designer Benedikt Gross. The pair ran aerial photos through computer imaging and human eyeballs on Amazon's Mechanical Turk to determine just how many pools there are in LA, while highlighting popular shapes and locations.

The idea for the project began while flying over the city, Gross told The Los Angeles Times, though didn't come to fruition until he met up with Lee at a Massachusetts Institute of Technology lab. Along with the printed research volumes (which aren't for sale), the pair created a 22-minute video of the pools and their locations using Google Street View, taking viewers on a journey to the fringes of the aquatic paradise hidden in plain sight.