It's the Marble Caves in Patagonia, Chile, which are known for their dazzling colors and pristine waters, and once you see them, chances are you'll start humming "Under the Sea." ...

Take the perfect road trip at the bottom of the world Glacial waterfalls, tropical plants, dolphins, marble caves: Patagonia’s remote Carretera Austral is an explorer’s paradise.

Another day trip is Queulat National Park, a stunning landscape of forests, waterfalls, fjords and El Colgante hanging glacier. Visitors can hike throughout the park and marvel at the untouched ...

The Marble Caves are accessible only by water, and they are best explored with kayaks, which enable visitors to wind in and out of the curved walls, according to the travel website Swoop Patagonia.

That means the erosion that formed the caves themselves probably happened quickly, shortly after the glaciers that carved Patagonia's iconic landscape began to recede. That was probably about ...