The spot in the Mile-High City that's exactly 5,280 feet above sea level (at least for now).

Fragments of architectural wonders from around the globe are embedded in the newspaper building's walls.

The origin of the Nixon tapes is rooted in technological incompetence as much as secrecy.

Chicago's Navy Pier on Lake Michigan was a training hub for aircraft carrier pilots during WWII.

Ohio's 19th-century communist micro-society.

This replica of an 8th century burial ship actually sailed to Norway before returning home to Minnesota.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

Ozymandias’ time-keeping temple.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

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

Daily jousts and dancing barrel makers in Munich's mechanical clock.

Beautiful Austrian natural history museum with carved ceilings and row after row of ancient taxidermy.

This splendid tomb may look fantastic, but there's nothing in it...

A small museum filled with over 1,000 clocks, and one particular clock calibrated to run until the year 9999.

Uh, pardon me, ma'am, but I couldn't help noticing that there's a Columbo statue in the middle of Budapest.

The bullet-banged DIY suit of armour belonging to Australia’s most famous outlaw.

A strange machine made to evaluate the world economy using water and lots of tubes.

Highly spherical boulders on the shores of New Zealand.

Possibly the world's largest coin stands just outside of a Canadian science center.

The ruins of a rehabilitation center for World War II vets can be found in the Westminster Ponds Conservation area.

The statue of the famous elephant who was the original source of the word "jumbo".

This massive mall has hundreds of shops, an amusement park, and a history of deadly amusement attractions.

It took over 100 years to decode this enigmatic epitaph for two buried brides.