This mundane post marks the old location of the city's main postal hub.

The Scottish Reformation leader's grave was paved over and is now a parking lot.

This museum houses two of Mexico's most impressive Aztec monoliths.

A striking depiction of Teotihuacan's mysterious "Spider Woman."

The largest outdoor art gallery in the Northwest United States.

Once home to an aristocratic family and a workers' organization, this intricately tiled building now houses a chain restaurant.

This 18th-century sundial was designed to calculate the date of Easter each year.

The ruins of the bathhouse used by the ill-fated last Aztec emperor still lie in Chapultepec Park.

This was once a hall in which a 16th-century royal banquet was hosted by King James VI of Scotland.

The final resting place of a German diplomat's beloved companion.

One of the figures in this Celtic sculpture continues to puzzle archaeologists.

This demon atop the Notre-Dame de Paris looks utterly bored.

Hollywood's oldest hotel is the site of the first Academy Awards, the birthplace of Marilyn Monroe's career, and the home of Montgomery Clift's ghost.

A labyrinth hides in plain sight at each of the city's 270 Tube stations.

This Viking gravestone carved in a rare runic style was dug up from a London churchyard.

It's a mystery why these remains were found with no traces of their bodies in sight.

This spectacular bridge is part of an abandoned train line that once connected Mallorcan capital to the southeastern coast.

An ancient water supply dating back almost 500 years can still be found standing in East Sussex.

The bones of two medieval royal lions were discovered at the historic fortress.

Ancient ruins hidden underneath a modern luxury hotel.

This giant temperature attraction created some giant electric bills.

Thrilling and delicious complement to any dining experience.

You won't find these curiously named passageways anywhere else in England.

These mysterious Viking chess pieces spent centuries hidden on a remote Scottish island.