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

Perhaps the most spectacular grotto along the Algarve coastline.

An underground city of salt.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

Beneath Kraków Old Town's main square lies a hologram-filled medieval market vampire graveyard wonderland.

This celebration of Latvia’s freedom and independence avoided demolition over half a century of Soviet occupation.

This charming Latvian lane doubled as Baker Street on the Soviet Union’s version of Sherlock Holmes.

The oldest housing complex in Riga is a mini timeline of architectural trends.

Flamboyant architecture from the turn of 20th century.

Latvia's symbolic mountain-shaped national library is home to millions of cultural tomes.

A black cat protests the City Guild in Riga's Old Town.

3,000 market stands in five former Zeppelin hangars.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

Inside this mansion turned museum, the works of prominent Croatian artists are on full display.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

Gargoyle head that brings good luck.

A beautiful mountaintop mausoleum devoted to a Montenegrin icon can't seem to make everyone happy.

One of the world's oldest olive trees, thought to be over 2,000 years old.

This exclusive resort has completely covered a tiny Balkan island in a 5-star warren of guest rooms.

Former military fort and site of untold horrors during WWII, this island may become the Adriatic's next luxury resort.

A tiny church on a man-made island in the Adriatic.

A curious little museum dedicated to the furry feline in the cat haven that is Old Town Kotor.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

This trio of Australian rock spires may have inspired aboriginal legend or just modern tourism.