LOS ANGELES, CA (Catholic Online) - The natural light show caused by the reflection of the azure water on the marble walls can only be described as breathtaking.

"It is the water that formed the unique shapes of the marble walls," landscape photographer and environmentalist, Linde Waidehofer from Colorado says. The 67-year-old photographer has her own volume on the caves entitled "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," she says.

Photography students have travelled from all over the world to learn from Waidehofer about light in what could be the "world's most astonishing classroom."

"Since 2003 I have taken many photography students into the caverns and it is always the highlight of their South American voyage," she says.

"The experience is always different because both the light and the water level of the lake are continually changing," Waidehofer adds.

The lake has an area of 1850 kilometers and borders between Chile and Argentina, dividing it roughly in half. Marble Cave is located approximately in the middle of the lake, on the Chilean side.

In Chile, the lake is called Lago General Carrera, and in Argentina, Lago Buenos Aires. Both of the names are internationally recognized. Lago General Carrera is one of ten deepest lakes in the world; with its maximum depth is 586 meters.

The lake is also surrounded by ridges of the Andes, and from the lake follows the River Baker, which flows into the Pacific Ocean.

"The water itself can vary from turquoise to deep blue depending on the weather and the time of year.

"In early spring the water of the lake is at its lowest point because the surrounding glaciers have not yet started to melt," Waidehofer says, "So the light will be reflected in a totally different way than later in the year after the melting glaciers have raised the water level over a meter.

"This changes what the visitor will see from the small boats needed to access these mysterious formations."

© 2012, Catholic Online. Distributed by NEWS CONSORTIUM.