Rock-hewn monastery complex with hundreds of cave structures tucked away into the mountainside.

This unique wooden mosque resembling a Chinese pagoda was said to be built without the use of nails.

The gravestone of a delicate singer-songwriter bears a fittingly introspective epitaph.

Mysterious spherical rocks in the semi-desert of western Kazakhstan.

Submerged trees jut ghost-like out of an idyllic turquoise mountain lake.

One of the most ethnically diverse spots on the planet.

Small church on top of a huge rock column.

Take respite inside this jaw-dropping church while climbing the volcano where Georgia's Prometheus was once chained.

A marvel of Byzantine engineering under the streets of Istanbul.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

Roman ruins top white travertine terraces formed by ancient hot springs.

This unique bridge is one of the last of its kind in Sweden.

A New York garbage depot holds a secret collection of weird and wonderful refuse.

Inaccessible by foot, Japan's most secluded train station sits in the middle of nowhere.

Wood carving meets bird conservation at this museum showcasing the life's work of one man.

A gardener's enduring labor of love is spread throughout a small Vermont town.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

This roadside stand packs 300-plus varieties of tomatoes, from "Maiden's Fire" to "Kaleidoscopic Jewel."

A field of nothing but boulders which resembles a giant's gravel driveway.

A reversed traffic signal that was once violently misinterpreted as a statement on British-Irish relations.

A Frankenstein blend of science and art allows one tree to produce 40 different types of stone fruit.

Surprisingly aquamarine waters fill deep lakes formed at the end of the last ice age.

Possibly the smallest church in the world floats in the middle of a pond.

This family-owned pottery shop is home to the last operational dragon kiln in Singapore.