One of the most remarkable caves in all of Iceland was created by a once raging river of lava.

A winding, blood-red tunnel of hardened lava navigable by foot.

Rising from the sea like a stone monster.

Medicinal spa created with the discharge from a geothermal energy plant.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

Staves, storm-calling, and of course, necropants.

An encyclopedic collection of mammal penises.

Bring your hiking shoes, wool socks, and thermal underwear for a stay in these cozy forest huts.

A series of modernist treehouse hotel rooms grace the outskirts of an Arctic forest.

Explore 10 acres of environmental sculptures.

Sacred Buddhist home of some spiritual monkeys.

This Balinese sea temple is thought to be guarded by the hundreds of monkeys that live around it.

Monuments don't get much more metal than these three giant viking swords planted in a Nordic hill.

Thriving meadows span a rooftop in one of Brooklyn's most heavily industrialized neighborhoods.

Eclectic architecture in the woods of New York.

A walkable map of the world, made from soil and stone by one man.

A tiny, forgotten park of surrealist sculptures in Angouleme.

A German town is growing a building out of trees.

At this unusual park, domes, ladders, chairs, and more are made from trees.

Artwork tucked within the trees greets visitors with surreal sonic experiences.

Hordes of precariously balanced stone figures crowd the shores of the Hudson River.

Hidden within a Netherlands crater is a stone bed that lets those who lie in it see the sky as a curved surface.

A stone circle on the slopes of a Caribbean volcano commemorates the leader of an anti-slavery uprising.

The rustic cabin-like decor of this Arts and Crafts-style church reflects the love of nature central to its little-known theology.