This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

The final resting place to 300 Victorian-era pets hides inside the city park.

Rebuilt remains of a temple to Roman god Mithras.

Hear the quietest sound from across the dome.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

An unusual round church in London with a Templar past.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

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

After the famous composer died in Paris, his sister snuck his heart out of the country to honor his wish that it be buried in their native country.

An underground city of salt.

In the midst of a living monument to Soviet social engineering, Polish Catholics built this church by hand.

This man-made mound monument was built out of soil from all across the Polish empire.

There are thousands of tributes and memorials to the King, but none quite like this one in a Kraków city park.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.

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

Real bones which are said to have belonged to a Polish dragon.