Go surfing on this urban wave, "hacked" by local surfers.

The fairy tale castle of the "fairy-tale king."

A castle from the Holy Roman Empire that hosts traveling youth... in its stables.

This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

This lurid German fountain plots the sad course of marriage from dating to death.

Originally envisioned by King Ludwig II to rival Versailles, Herrenchiemsee's "New Palace" remains half-gilded for lack of funds.

The beautiful, ornate weather station is the most popular geocache in Salzburg.

A small marionette collection located within the dark cellars of an 11th-century Austrian castle.

The medieval network of canals hidden underneath the city is opened to explorers each year.

This skeleton-filled altar piece served as a backdrop to one of the most iconic scenes in "The Sound of Music."

The last moments of the ill-fated Pompeiians, frozen forever in plaster.

Erotic art covers the walls of the largest ancient pleasure palace.

The largest greenhouse in the world is home to over one million types of plants.

400-year-old garden, restored to beauty.

A fantastic castle rumored to be the birthplace of King Arthur.

Northern Ireland's Brobdingnagian stepping stones.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

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

The remains of an ancient Roman teenager are memorialized at the base of a modern London landmark.

Black cat statues guard this temple-like Egyptian revival factory.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

An unassuming London park is actually a pilgrimage site for modern clowns.

This 1920s Dutch barge is now a floating bookstore.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.