Mountains

A mountain pass in Bulgaria's Balkan Mountains was the site of four historic battles.

This super steep hike ascends 2,000 feet in less than a mile.

High in the clouds of San Marino sits an ancient tower with some curious prisoner graffiti.

At nearly 1,000 feet long, this astonishing glass suspension bridge is one of the longest in the world.

A favorite with sightseers and locals alike, this Norwegian funicular provides easy access to a stunning view of Bergen and its environs.

Traversing steep Alpine slopes, this engineering marvel is one of the longest and highest funiculars in the world.

A subterranean playground in an abandoned slate mine.

Réunion Island's highest point is a two-million-year-old volcano and a paraglider's paradise.

This subterranean funicular is one of the world's smallest subways.

Caves full of Buddhist statues, incredible rock formations and a deserted lagoon.

An icy lake tucked among jaw-dropping alpine panoramas.

For two weeks every June, fireflies in the Smoky Mountains perform an astonishing light show.

The unique ecosystem atop an Australian mountain is home to some colorful inhabitants.

Teddy Roosevelt’s famous “midnight ride to the presidency" started at this small lake high up in the Adirondacks.

Remote, beautiful, and stigmatized, Las Hurdes is Spain's version of Appalachia.

This vertical pinnacle in China was the inspiration for the floating mountains in the movie “Avatar.”