This ancient Irish tower could easily have stood in for Rapunzel's prison.

After being destroyed by IRA sympathizers, the ruins of this stately Irish manor have sat vacant for decades.

This single room has survived the centuries with almost no deterioration.

There might not be much left of these Irish ruins, but their linguistic legacy is still going strong.

The oldest inn in Kilkenny was established by the first convicted witch in Ireland.

Obelisks and stone pineapples in the Irish countryside.

One of the most popular megalithic sites in Ireland stands as a humbler version of Stonehenge.

This ancient Irish religious site is covered in ancient carvings, many of which have barely aged.

The ancient tomb acts as a calendar that keeps perfect time.

This small exhibition displays equipment and artifacts once belonging to the feared Stasi secret police.

The sweet story of how American cargo planes became known as "Candy Bombers" during the Berlin Blockade.

This wooden hotel is a temple to German sustainability and forest conservation.

A century-old shot ball factory tower is open to the public once a year.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

It's good luck to be mocked by this monkey.

Cold war icon and onetime "hole" in the iron curtain.

Hamburgers are intensely proud of their tunnel beneath the river.

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

This water-tower-turned-high-end-apartment building was once the site of an early Nazi concentration camp.

Berlin's old airport.

A fascinating insight into daily life in the Eastern Bloc.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

The 1936 Summer Olympics site is a crumbling remnant of sportsmanship and a history its host country would like to forget.