This celebration of Latvia’s freedom and independence avoided demolition over half a century of Soviet occupation.

This unique historical monument features large concrete spheres designed to resemble fallen stars.

A public art jibe at one of the United States’ oldest and longest-serving senators.

The ruins of the largest gladiatorial school in Rome are largely hidden under modern streets.

Dedicated to the victims of one of the deadliest hurricanes to strike the United States in recorded history.

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

The ruins of this ancient fortification wall sit in the middle of a quiet, residential intersection.

The Great Fire of London and the regulation of one-way streets both started in this alley.

This hill and tower are steeped in legend, from King Arthur to the Holy Grail.

This equestrian statue of Constantine the Great has been the subject of criticism for centuries.

The reconstruction of this prominent building fulfilled a long-written command.

Atop this media building, two hives containing more than 30,000 bees keep the surrounding area vibrant.

Disks are rolled out onto the south lawn to absorb the impact of Marine One's wheels like giant coffee coasters.

An 18-mile-long tunnel for sewage waste will soon wind within the bowels of Washington, D.C.

Daredevil repair workers can worm their way out the access hatch, loop ropes over the apex and rappel down the monument.

The monument's pointy aluminum tip has been melted down by repeated lightning strikes.

The most accurate timepiece in the world.

This restaurant has been a haven for D.C.'s LGBTQ community since the 1950s.

The site of the climactic scene from the classic horror film is now a historic landmark.

Obscure Freemasons still live in D.C.’s largest private residence.

This stately mansion, built in 1787 by America's first Secretary of the Navy, is rumored to be one of the most haunted buildings in Washington, DC.

This robust fence in front of a historic Georgetown home is likely made from hundreds of recycled Revolutionary War firearms.

This grand gothic brewery has been pumping out suds for over a hundred years.

A Spiritualist house of worship where believers communicate with the dead in the spirit world.