The Marble Caves are located on Lake General Carrera/Buenos Aires (Depends which side of the lake you are on) Patagonia, Chile, near Puerto Tranquillo (a little town), Río Ibáñez. The amazing vibrant blue and grey cave chambers, (submerged to some extent) all lay in memorizing turquoise waters of Carrera/B.A Lake. formed by waves over 6000 yrs.
The Marble Caves of Patagonia, Chile, are beautiful vibrant blue caverns, partially submerged in the equally stunning turquoise waters of Carrera Lake. Description from edotmagazine.com. I searched for this on bing.com/images