Roughly 17 million letters to Santa have found their way to this Arctic Circle post office.

This unique zoo is the only place in the world where you can see all 15 species of crane.

Crossing this suspension bridge feels like walking through the sky, a fitting tribute to the head of the Apollo program.

Now famous as the "Harry Potter bridge," this impressive concrete viaduct has long been an icon in its own right.

A brightly colored natural bridge formed by mineral-rich hot springs high up in the Andes.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

This hulking behemoth is actually five interconnected towers built in the 1960s.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

A remote candy-striped mountain in the Peruvian Andes straight out of the pages of Dr. Seuss.

The birthplace of an eccentric alchemist and possible inspiration for the fictional reanimator of monsters.

Morocco's Argania trees are infested with nut-hungry goats.

On the Oregon coast there is a natural hole that seems to be draining the sea.

An isolated dive site teeming with cnidarians.

A massive underwater sinkhole made famous by Jacques Cousteau.

For divers and music lovers, the Florida Keys' Underwater Music Festival provides the best of both worlds.

During the solar phenomenon "Lahaina Noon" this bendy, curvy sculpture forms a perfectly circular shadow on the ground.

This dramatic sea spire is home to the world's rarest insect and is part of the lost continent of Zealandia.

A lovers' beach, tucked below the surface of the island, provides a safe haven for romance.

On Japan's Tashirojima Island, cats are king.

The world's oldest individual clonal tree looks like a wimp despite standing tall for 9,550 years.

A magically clear, blue river that seems to spring from nowhere.

This eye-popping Icelandic crater lake is surrounded by red volcanic rock.

This massive chapel in the middle of the Indonesian forest is both haunting and fowl.