Media Luna or Half Moon Lake is located in the Mexican state of San Luis Potosí in the high semi-arid plateau of the Sierra Madre Oriental Mountains at an altitude of 982 m (3,222 ft). The lake’s warm water 28-32° C (85-88° F) and great visibility 20-30 m (60-100 ft) makes it a perfect place to continue your dive training, gain more diving experience or just to add a new experience to your dive log. And, because of its protected status as a national preserve, the thriving wetlands contain considerable biological diversity for the photographer and naturalist alike.

The lake is fed by five different thermal springs with a flow rate of 4.35 m3/ second. The flow is so constant that the warm clear water is used for irrigation for over 5,000 hectares of farmland. As mentioned, these thermal vents give Media Luna a constant warm temperature, but because of the lake’s arid location, you can quickly chill upon surfacing with the slightest of breeze.

The lake itself is of a moderate size with a maximum diameter of no more than 100 m (330 ft) or 25 hectares and an average depth of 9-12 m (30-40 ft) and a maximum depth of 34 m (110 feet). The deepest portion of the lake is in the center but that depth is not maintained throughout. Please remember, because it is spring water, the mineral content is higher than most freshwater sites which will increase your buoyancy so make sure and bring extra weight.