Vaalserberg

An impressive century-old, to-scale topographical map of Guatemala.

A remote Arctic mountain range is home to "granite cities" found almost nowhere else.

A narrow fjord-like lake, the third-deepest in the United States, runs for over 50 miles into the Cascades of Washington state.

These rugged, color-stained mountains hold the secrets of the Kazakh desert.

Visit Europe's largest subterranean waterfall, carved by water from the glaciers of the towering peaks surrounding the valley.

The "Grand Canyon of Southwestern Idaho" makes a spectacular gash across the flat Snake River plain.

A small mountain made entirely of banded iron stone overlooking downtown Ishpeming.

The top of the holy mountain for the ancient Spartans looks like a pyramid—is it man-made or a natural phenomenon?