A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Eighty million natural history specimens call this gargantuan museum home.

Giant, friendly pelicans in Central London, the most unlikely of places.

The sixth of London's "Magnificent Seven" cemeteries, and a source of unlikely inspiration to Beatrix Potter.

The remains of Crystal Palace Great Exhibition of 1851.

Abstract dinosaur models in London.

Go inside to really appreciate this 500-year-old technological masterpiece.

Northern Ireland's Brobdingnagian stepping stones.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Hauled from the water's depths, Henry VIII's flagship is preserved in this capsule-shaped museum.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

Cold war icon and onetime "hole" in the iron curtain.

The site of the famous Nazi book burning campaign of 1933 remembers its "Night of Shame".

An underground city of salt.

This Slovak bridge is known both for its connection to a national uprising and its UFO-shaped eatery.

Budapest's Communist-era statues, banished to the suburbs.

Museum dedicated to the terror regimes of Hungary.

The final resting place of soldiers' loyal canine companions.

A six-ton wedding present for the King of the Scots.

360° views of the city plus five floors of optical illusions and hands-on science.

A 18th century graveyard and its astonishing cortege of macabre iconography.

Cozy basement bar sports an inventory of over 2,000 beers.

Where commuters walk through remnants of an ancient Greek necropolis.

This $62 million dollar temple was erected to house one little dental fragment of religious history.