The vast, legendary catacombs hold secrets much stranger than stacked bones.

France's national museum of scientific and industrial instruments.

The celebrated eyesore created by starry-eyed sweethearts.

The video game-themed street art first popped up in the French city.

In Midtown Atlanta, tons of marble appears to be devouring a Fiat Panda at this unique art installation.

This stone is a marker of one millionaire's personal vendetta against gravity.

This massive store is home to an eccentric collection of vintage, retro, and peculiar goods.

An underground magnet for ever-changing street art.

In upstate New York, gorgeous waterfalls and a watermill are slowly being reclaimed by nature.

Dedicated to the art and science of glass in equal measure, this space is as much laboratory as museum.

One of the Seven Wonders of the Modern World holds the world's tallest metal staircase.

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

The former hotel where Tesla invented the radio.

This upscale streetwear store is hidden behind a fake Snapple machine in the back of a deli.

Statue commemorating the use of ether in anesthesia.

A men’s restroom became a sandwich shop.

Mrs. Mallard and her brood are a beloved fixture in Boston Public Garden.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

This valley of hot springs and boiling mud pots is home to the record-holding "Geysir," which originated the English word.

An Icelandic island full of diving birds and legend.

Instead of solid circles, the stoplights in this northern Icelandic town have glowing red hearts.

This elegant arc of a waterfall marks a religious turning point.

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

Millions of numbers carved in glass represent the tattoos forced upon victims.