Lake Lácar, situated at 630 metres above sea level inside Lanín National Park, is one of the warmest high-altitude lakes in the Andes: summer water temperatures reach 19-21°C, making it unusually comfortable for altitude diving. Average visibility is 20-25 metres — exceptional for a mountain lake — with glacial-origin floors and remarkable water clarity.
Because of its elevation, Lake Lácar is classified as an altitude dive site, requiring decompression planning different from sea-level standards. In winter the temperature drops to 7-9°C and a drysuit is recommended. Underwater fauna includes brown and rainbow trout, freshwater clams and river crabs. The lake offers discovery dives for beginners and exploratory dives for certified divers.
The Club Náutico San Martín de los Andes (CNSMA) is a nationally recognised sports diving entity (Argentine Naval Prefecture licence No. 19), and Oceanica Buceo offers guided dives and courses on the lake. Best season is December to March, making the most of the warmest water.
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