The grand complex of buildings that comprise Liverpool's Exchange Flags includes a vast World War II bunker that has been frozen in time.

Most of Britain's gold reserve was secretly stashed here after the start of World War II.

This bronze statue was dedicated to a 1966 Beatles hit.

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

Two stone columns flank the grand Venice square, but there were supposed to be three.

Thousand-year-old Viking runes adorn an ancient Greek lion at the entrance to the Venetian Arsenal.

This Venice bookstore has resigned itself to constant flooding by keeping its books in bathtubs and boats.

The walls and streets of the ancient city are peppered with penises.

Ancient snack bar of the Roman Empire re-opened.

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

The widest natural waterfall in Estonia is a sight to see in all seasons.

This secret coastal village is studded with pastel-colored houses all piled on top of one another.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.

This stunning limestone waterfall is the highest in Estonia.

Its collection offers a glimpse into the Russian Old Believers' centuries-old way of life.

This former medieval prison now unlocks Estonia’s rich photographic history.

This off-beat, quirky communism-themed bar isn't afraid to poke fun at its history.

On Gellért Hill, this statue depicts the tragic tale of lovers divided by the Danube.

This gem from the industrial age helps visitors and residents alike traverse hilly Stockholm.

Visitors can sit and study the board with this Estonian chess legend and International Grandmaster.

A large boulder was declared a local landmark by a popular vlogger.

The Guardian of Tallinn.

The oldest church in the Estonian capital is home to over 100 fantastical cemetery coats-of-arms.

Only a fragment of this 15th-century Dance of Death survives today.