The partially submerged ruins of a white marble quarry used in ancient Greece for over 1,200 years.

Iceland's tribute to its thankless civil servants.

Built by the Ancient Greeks, this chariot bridge is still in use today.

Its unique collection details the history of the state's svelte railroads.

These ruins of a sacred Ancient Greek temple stand next to a luxurious modern resort.

This beehive tomb built for royalty sat hidden for over 3,000 years.

A section of the long chain that blocked enemy ships from entering Constantinople.

The ruins of an ancient Roman tomb hidden in the basement of a trendy clothing store.

Two Ming Dynasty lion statues guard the entrance to the journalism school.

The obelisk meant to mark the founding father's grave at Monticello is actually on the University of Missouri campus.

The railway carts travelers to central Athens's highest peak, which offers stunning vistas of the city.

The monumental steeple on Amherst College's campus has no church attached to it.

One philanthropist's extensive collection of knick-knacks and curiosities is now a public museum of oddity.

There are many Byzantine-era churches still standing in Athens, but this is the only one with a 2,500-year-old column rising through its roof.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

An ancient octagonal weather station named for the eight Greek gods of wind.

Behind medieval walls in a corner of bustling Palermo is a breathtaking former mosque once inhabited by a wolf-taming hermit.

A Byzantine church containing the holy remnants of three saints sits atop the site of an ancient temple.

The only surviving choragic monument is a trophy awarded in 334 BC for the winning dramatic chorus.

This blue behemoth of a bear is a colorful homage to Brown University's mascot.

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

Memorials at a Florence railway station remember the citizens who were deported from Italy and sent to extermination camps.

This amazingly preserved Doric temple was abandoned before it was ever completed.

The ruined doorway is a portal to the building's turbulent and torturous past.