Sacked by Vikings, blessed by William the Conqueror, dealt a fatal blow during the French Revolution—these ruins have seen it all.

Explore the complex ecology of this multifaceted nature preserve by riverboat.

A French valley with forests so lush it was nicknamed "the Small Amazonia of the Pyrenees."

A site where “the ravages of the war are more striking…than any other place in contemporary Spain.”

An unusual slot canyon in the Aztec/Navajo Sandstone has a cross-section like an inverted old-fashioned keyhole.

These unique "earth pyramid" clay columns can be found in ravines around the village of Tirolo.

This horseshoe-shaped waterfall is the second-largest on the African continent.

In the heart of Luxembourg's "little Switzerland" weaves a breathtaking natural sandstone canyon with a mythological past.

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

Internet rumors, often involving Icelandic singer Bjork, have abounded regarding this isolated outcrop of rock.

Europe’s most powerful hot spring supplies the surrounding region with hot water.

Climbing Iceland's highest peak on the rim of the Oræfajökull volcano.

This canyon is comprised of gorgeous waters and magnificent basalt columns.

Iceland's largest geothermal mud pool is a little bit haunted and a little bit dangerous.

Puffin enthusiasts flock to Europe's largest seabird cliff, which over one million birds call home.

Two volcanic lakes in an enormous crater formed in a prehistoric eruption.

The bright red stripes streaking across the rocks are the star feature at this Icelandic waterfall.

This black church sits alone among a field of lava rock.

This mountain fissure hides a secret path to a secluded mossy grotto within the rock itself.

This fairytale-like structure is the last turf church ever constructed in Iceland.

Surrounded by ash fields in Iceland, an impossibly verdant valley looks like something out of a fairytale.

This hobbit-y little hot spring may be the oldest spring used by humans in all of Iceland.

These ominous lava formations were said to be an entrance to the netherworld so of course they inspired a famous metal band.

The oldest church in Iceland is one of the few to feature ornate decoration.