A Turkish monastery tucked into a cliff wall.

Hindu temple of the dead home to hundreds of long-tailed macaques.

This one-time health resort was used by aristocrats around the world.

This Armenian monastery was carved out of cliffs and named after the spear used to stab Jesus.

A modern temple with an ancient philosophy.

Small church on top of a huge rock column.

A dangling church built over a Colombian gorge.

Once an impressive link to Afghanistan’s Buddhist past, now a sad reminder of intolerance towards other cultures.

Highly unusual subterranean stupa and adjacent cave monastery.

An ancient jungle temple carved into a rocky overhang of the Dane Soung Plateau.

Numerous sculptures set along hiking trails symbolize and idealize the relationship between man and nature.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Massive series of 45 caves and over 51,000 sculptures carved from cliffsides in China.

A curious cave church carved into the face of a cliff.

One of the world's largest salt caves is filled with fragile salt sculptures, salt rivers, and huge salt megadomes.

Inside this mountain lies several kilometers of breathtaking caves.

Hundreds of caves once used to store grains and animal feed.

A 10 million-ton rock once worshiped by the Tahamies Indians, accessed by an astounding staircase.

A fantastical group of cliffside stairways, bridges, and twisting paths carved out of stone provide a surreal coastal hike.

Rock-cut cave complex filled with ancient Buddhist artwork.

This complex of vertically-excavated Buddhist, Jain, and Hindu monolithic temples in India's Maharashtra providence illustrates a spirit of tolerance characteristic of ancient India.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

These faux-cliff dwellings allow visitors to climb around on a replica archaeological site.

The largest cave shaft in the world is home to thousands of birds and popular with BASE jumpers.