Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

A fantastic place to see murals, and an important location in the history of Toronto's legal street art scene.

Its columns were all carved from the same white oak tree.

A historic Montreal market that was the city's agricultural hub for over century.

The last holdout of a pre-Civil War rebel who took the matter of slavery into his own hands.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.

Despite its lavish ornamentation, and wholesome lifestyle of its devotees, this mountain commune has faced its share of issues.

Beyond the usual stories that attend old prisons, this one has deep bloody undercurrents.

It was once the base for a series of domestic terror attacks.

An amazing example of early-20th-century architecture, this church features marble transported from Utah.

The 5.5-mile ring of steel posts around the Capitol Building is one of the largest (and most uniform) of its kind in the world.

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

A 1,100-ton train fell through the floor in 1953. Workers got it patched up in just 72 hours.

A derelict bit of infrastructure from the canal that once ran through D.C. is landlocked in the heart of the city.

A hidden passageway now marks the site of an assassination attempt on Ronald Reagan that some say broke a 140-year-old curse.

A muscular Art Deco monument represents the struggle between regulators and unbridled markets.

While most wind tunnels test scale models, the "Cave of Winds" was large enough for actual airplanes.

Look closely and you’ll notice that the color changes a third of the way up the tower.

The little-known, 300-year history of the area includes former lives as a bustling tobacco port, parking lot, and industrial dump.

Architecture lovers won’t stop touching the National Gallery's 19.5 degree marble prow.

Legend has it that President Grant’s frequent drinking in the lobby gave rise to the term “lobbyist.”

Washington's iconic carousel has a nice piece of Civil Rights history.

The "lovely red Vega" of the legendary record-settling pilot.