Chile's Color-Changing Caves Are Stunning. Here's What You Should Know

Right at the point where Chile meets Argentina on General Carrera Lake, there sits a natural wonder like no other. A series of caves that resemble blue marble stretches far and wide (via Atlas Obscura). These caves are a fascinating find for those daring enough to embark on the journey, which is an arduous aquatic adventure.

The narrowness of the archways and columns means it is only possible to explore this hidden gem by sea, and on a tiny vessel, nonetheless (via Ten Random Facts). However, that venture might be worth it as Cuevas de Marmol, or in English, the Marble Cave, has been coined the "most beautiful cave network in the world" (via When on Earth).

In the glow of its glacial surroundings, the Marble Cave network, or Marble Cathedral, looks a bit like a sculpture set on ice — a result of water- and weather-related erosion. Ever-changing in its appearance, this stunning series of caves has been undergoing an ongoing makeover for approximately 6,000 years.

Both in their creation and in their appearance, the Marble Caves reflect the transition of the water surrounding them on all sides (via The Travel Specialists). As that water eroded the calcium-rich marble stone, the waves, like sculptors, shaped the structure. 6,000 years of splashing later, and the gaps that were once cracks are now large enough to be walkways and water tunnels.

But, the caves' majestic relationship with the water of General Carrera Lake doesn't end there. The walls of the Marble Cathedral also take on the hue of the water below, which means the walls are a different color depending on weather and season. Depending on when you choose to spelunk through, you might view these caves in a shade of cobalt blue, turquoise, emerald, pink, or muted gray (via Travel Awaits). This natural phenomenon occurs as glaciers freeze and melt and sea levels rise and fall throughout the year.