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

3,000 market stands in five former Zeppelin hangars.

Flamboyant architecture from the turn of 20th century.

The holes in this wall provide a glimpse into Jewish life in Budapest, both past and present.

From cartoon characters to tiny tanks, a guerilla sculptor's little bronze statues are hidden throughout the city of Budapest.

The true meaning behind this sculpture remains unknown.

The metal leaves on this tree are engraved with the names of Holocaust victims.

A 13th-century convent where St. Margaret of Hungary spent her teenage years.

Some of the greatest minds in the history of Hungarian art and science converged in this café.

A two-way chairlift system between Zugliget and the highest point in the city.

Late at night, the bust of the "Dracula" actor was snuck onto the facade of this Budapest castle.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

Museum dedicated to the terror regimes of Hungary.

Once the home of a hermetic monk, this cave now houses a small church.

Built in 1870 at the bridge that connected Buda and Pest, this spectacular incline railway was almost lost forever during World War II.

This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

A trail of iron footwear stands as a monument to the thousands executed along this riverbank during WWII.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

Millions of numbers carved in glass represent the tattoos forced upon victims.

A former waterfront market is now in the center of town due to some interesting Boston engineering.

One of the indelible moments of the American Revolution took place at this location.

This nearly 200-year-old restaurant's history includes an exiled French prince, JFK, and a very hungry Daniel Webster.