This spectacular Marble Cathedral, an intricate system of water-filled caverns, is set in the General Carrera lake in Chile's Patagonia - the second largest freshwater lake in South America.
But to reach this remote place, located in the far southern tip of the country, visitors must fly from the capital Santiago, 800 miles to the next nearest large city, Coyhaique, and then drive on challenging dirt roads 200 miles south to the lake.
But the journey is worth it for many visitors, who believe the light show caused by the reflection of the azure water on the marble walls is unparalleled anywhere else in the world.
This incredible set of pictures has been captured by landscape photographer and environmentalist, Linde Waidehofer, 67, from Colorado, USA.
'It is the water that formed the unique shapes of the marble walls,' explained Ms Waidehofer in her book on the caverns, Blue Light.
'Originally great ice-fields blocked the western end of the lake - today its glacier-fed waters drain into the Pacific Ocean.
'Geologists have a simple explanation for the breath-taking blue of this giant lake.
'They talk of finely ground glacial silt which makes the water an unearthly blue and crystal clear.