Learn about Iceland's hidden folk at this school dedicated to the study of elves.

One of the oldest family businesses in Reykjavík serves lamb-based hot dogs.

This aromatherapy shop and mini-museum cofounded by the Sigur Rós frontman documents Icelandic history through scents.

Celebrate the history of the rich and truly misunderstood relationship between man and pigeon.

This fantastical waterfall is hidden in a cave located in a cracked cliff.

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

A little-known, yet charming glacial lagoon.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

This memorial honors thousands of enslaved Africans and their descendants who died in colonial New York.

The 2,000-year-old beam is tucked within the pedestrian entrance to the old London Bridge.

Only a few pieces remain of the structure that carried people and goods across the Thames for some 600 years.

A tiny replica of the iconic London landmark hides on the side of the steel structure.

What started as a way to address damp basement walls turned into a house filled with intricate hand-carved designs.

A fully functional, 200-year-old remnant of the time when Brixton was mostly fields.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

This coffee shop lies hidden beneath a historic church.

Since 1887, this old-school shop has stacked its shelves with extraordinary coffees and teas.

A Roman spa buried deep beneath the City of London.

Claiming to be the oldest hat store in the world, this historic haberdashery had a hand (and a head) in the creation of the Bowler.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

A hidden treasure in London with a rich medieval history, and the resting place of many luminaries.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

Scattered throughout London are ancient remnants of the city's former bounding wall.