If you’re a fan of cenotes, or underground sinkholes, you should probably head on down to Mexico ASAP.

There are some 6,000 of them along the country’s Yucatan Peninsula, mostly around Tulum. The Mayans believed they were sacred gateways to the underworld, and whileyou may still find relics of their sinister past, these days you can visit the crystal clear waters for snorkeling, scuba diving, and swimming.

Here are a few to consider for your next trip.

Cenote Dos Ojos
dos ojos cenote
A great cenote for scuba divers and snorkelers about 15 minutes north of Tulum, with water temperatures in the mid-70s year round. Accompanied by a guide, divers can navigate through the dark passages and surface in an air-filled bat cave.

Gran Cenote (Sac Aktun)
gran cenote
Arrive at this popular cenote early to avoid large crowds of tourists, who come for its clear waters and near perfect visibility.

Cenote Carwash (Aktun Ha)
cenote carwash
Once used to wash taxis along the highway to Coba, this striking cenote is now a favorite among photographers for its beautiful vegetation and underwater rock formations.

The Pit Cenote
pit cenote
As the deepest known cenote in the area, the Pit is perfect for more experienced divers. With unlimited visibility, the aquamarine shafts of light penetrate the depths for a truly magical sight.

Cenote Angelita
angelita cenote
Dive about 100 feet to see Cenote Angelita’s underwater river, an illusion that occurs when denser saltwater sinks below fresh water. Check out Anatoly Beloshchin’s breathtaking photos of the phenomenon.

Calavera Cenote
calavera cenote
Calavera Cenote, also known as the Temple of Doom, is just a 5-minute drive west of Tulum. It gets its ominous name from the three circular openings on the cave roof that resemble a human skull.

Ik Kil Cenote
If you manage a side trip to Chichen Itza, be sure to make a stop at this stunning cenote located in the Ik Kil Archeological Park.

Cenotes Choo-Ha, Tamcach-Ha & Mult?n-Ha
coba cenotes
Swing by these three cenotes for a refreshing dip after visiting the Coba ruins, about 30 minutes from Tulum.