The bridge is a secret gallery of discarded gum that has been transformed into miniature masterpieces.

This one has sailed five times as far as Sir Francis Drake's famous ship.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the first ‘Harry Potter’ film.

The Great Fire of London and the regulation of one-way streets both started in this alley.

The commemorative stone column conceals a secret laboratory.

A tribute to the intrepid explorer and his crew who perished in terrible conditions on an ill-fated expedition to the Arctic.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

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

Never actually a tree at all, this spot was the site of London's public hangings for nearly 600 years.

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

Once designed as the entrance to Buckingham Palace, this structure was later relocated and stands as a victory arch.

London's smallest police station is barely the size of a phone booth.

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

A monument to the thrice mayor of London who according to lore made his fortune by selling his rat-chasing cat.

The sculpture of the deceased cockatoo flops atop its personal plinth.

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

A mysterious shape catches the eye in this 16th-century painting.

The television series' iconic giant foot was borrowed from this classical painting.

The world's most active stratovolcano is almost always erupting.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.

Quite possibly the oldest love poem known to humankind.

A small etching on the white marble parapet was written in runic script by a Viking mercenary.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.