Cenote Zapote (Hells Bells) Swim and Dive

Cenote Zapote, known as the Hells Bells cenote, is a freshwater sinkhole on the Ruta de los Cenotes near Puerto Morelos in Quintana Roo, Mexico, roughly 35 to 45 kilometres from Cancun. It is best known among divers for the Hells Bells, unusual bell-shaped stalactite formations that grow downward from the cenote floor at depth and are visible only to certified divers. The formations sit far below the surface and are reached on guided technical-style dives, so non-divers do not see them. The cenote also offers swimming from the surface for visitors without dive training, with a jumping platform and clear water in the open sinkhole, which makes the site a mix of casual swimming and advanced diving. A typical visit lasts two to three hours. Swimming needs only basic confidence in deep water, although lifejackets are commonly available, and minimum ages are set by the operator. Diving requires proper certification, and visitors who want to see the Hells Bells should expect to demonstrate a suitable qualification and logged experience to the dive centre, since the deeper zone involves a chemical layer, low light and depth limits. Certified divers can rent tanks and equipment on site; other guests bring a swimsuit and towel. Sunscreen and insect repellent are not allowed in the water, so visitors usually rinse before entering to protect the cenote ecosystem. The operators brief swimmers on entry points, depth and not touching the formations, and divers receive a dive plan covering depth, gas management, turn pressures and ascent procedures. Rescue relies on on-site staff, oxygen and first-aid supplies, and transport to clinics or hospitals in Puerto Morelos and Cancun. The cenote is open year-round, but crowds are lower from November to April. Heavy rain can reduce clarity and make the access paths slippery, and the wet season from June to October carries the strongest storms.