Cypress swamps can be found throughout the Everglades, but the largest covers most of Collier County. The Big Cypress Swamp is located to the west of the sawgrass prairies and sloughs, and it is commonly called "The Big Cypress".[66] The name refers to its area rather than the height or diameter of the trees; at its most conservative estimate, the swamp measures 1,200 square miles (3,100 km2), but the hydrologic boundary of The Big Cypress can be calculated at over 2,400 square miles (6,200 km2).[67] Most of The Big Cypress sits atop a bedrock covered by a thinner layer of limestone. The limestone underneath the Big Cypress contains quartz, which creates sandy soil that hosts a variety of vegetation different from what is found in other areas of the Everglades.[66] The basin for The Big Cypress receives on average 55 inches (140 cm) of water in the wet season.[68]