Cenote water is often very clear, as the water comes from rain water infiltrating slowly through the ground, and therefore contains very little suspended particulate matter. The groundwater flow rate within a cenote may be very slow at velocities ranging from 1 to 1,000 meters (3 to 3,000 ft) per year.[citation needed] In many cases, cenotes are areas where sections of cave roof have collapsed revealing an underlying cave system, and the water flow rates here may be much faster: up to 10 kilometers (6 mi) per day.

 

 

 Cenotes around the world attract cave divers who have documented extensive flooded cave systems through them, some of which have been explored for lengths of 100 km (60 mi) or more