The extra platform at Gloucester Road has been used for art displays for over 25 years.

An extensive, if one-sided, history of U.S. law enforcement's war on drugs.

Public opinion is still divided on this enormous sculpture in front of Baltimore's Penn Station.

This Asian-inspired tower in a lush urban park provides spectacular panoramic views of Baltimore.

A gorgeous, Gaudí-esque stairway constructed in the city of Istanbul by a prominent Jewish family.

Climb a steep hill in 90 seconds on the second-oldest urban subway in the world.

Five sultans and their families rest in eternal splendor, teeming with overlooked beauty and drama.

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

These ornate arches show how the course of the River Thames has changed.

A totem pole of heads to represent the different stages of life.

The arching stretch of London's longest street holds many reminders of the area's maritime past.

The first tunnel to be dug beneath a river, repurposed as an art and museum space.

This pump on the bad side of Victorian London betrayed a horrifying revelation about the water supply.

A historic arboretum and non-conformist, non-denominational park cemetery.

Giant, natural amphitheaters made of delicate geological formations called "hoodoos."

Site of the first hot air balloon flight conducted by the first English balloonist.

Originally founded in 1654, this coffee house claims to be the oldest of its kind in Europe.

The East Village tenement from the cover of Led Zeppelin’s 1975 album has a tea shop on the ground floor.

Pulled from the rubble of one of the worst modern tragedies, a steel crossbeam became a symbol of hope for New Yorkers.

The most confusing clock in New York.

This historic building housed the surviving crew members of the Titanic, who were left destitute after the wreck.

The iconic Manhattan corner that was once the site of the Beastie Boys' fake clothing store.

Visit the monolithic tomb of America's most famous general.

Avoid gangster interaction while window-shopping.