This restored 17th century "conduit house," often mistaken for a watchtower, actually supplied water to nearby Bolsover Castle.

One of the last remnants of the Bessemer process that revolutionized steel production during the industrial age.

Though they've since been renamed, these two streets hint at Dublin's darker days.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

The oldest surviving botanic garden in the United States.

A headstone notes where the most famous of Robin Hood's legendary Merry Men is reportedly buried.

This oddly placed 15th-century church is one of only six bridge chapels left in England.

One of the shortest streets in York has an especially odd name.

The UK's largest private house was the subject of a long-lasting political dispute.

The gaunt visage of this angular Christ giant is enough to put the fear of God into all who see it.

This open air archeological site houses almost as much wildlife as it does classical religious artifacts.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

D.C. once had its own tiny rival to the New York Stock Exchange.

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

A medieval relic whose great hall once hosted Mayflower pilgrims, one of Henry VIII’s ill-fated wives, and plenty of royal intrigue.

An oddly shaped tower built to mark the acquittal of Admiral Keppel in a controversial 1770s case.

Fittingly, America's museum of architecture is itself a magnificently designed old building.

This chain of artificial lakes was an ideal test ground for the aircraft that would carry the "bouncing bombs" used by the WWII "Dambusters" squad.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

Free public park and gardens filled with peacocks and peahens.

DIY collection of eclectic holdings.

One part antique store, one part curiosities hodge-podge.