A 98-room castle in the middle of Toronto that bankrupted a 19th century electricity multimillionaire.

This historic fort spans more the 300 years.

This impressive working clock made of 16,000 plants changes its flowers twice a year.

A huge musical instrument played by the ocean.

Found art has transformed this Pittsburgh neighborhood into a psychedelic dream.

The only depiction of Abraham Lincoln holding a weapon, and the names of all 9,000 Cuyahoga veterans of the Civil War.

This spectacular public market has got meat, fish, vegetables, baked goods, and enough kielbasa for a lifetime.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

This American Civil War-era fort still stands near the border between Washington, D.C. and Maryland.

Hidden beneath the streets of London is a secret subway that only carried mail.

Legend says these rocks used to be hunting dogs, a story that may have inspired Sherlock Holmes' most famous case.

The smallest island in Manhattan is a manmade landfill dominated by a Buddhist peace arch.

A memorial to the victims of Argentina's "Dirty War."

105-foot wide giant metallic flower blooms anew every day in the heart of Buenos Aires.

Museum housed in underground tunnels that date back to Buenos Aires's earliest settlements.

A bright little alley in La Boca is a part of tango history.

This historic, palatial theater is now one of the world’s most beautiful bookstores.

Buenos Aires' city of the dead contains some very famous remains, including Eva Perón.

The humble tomb of an Argentine general, hand-built by his son using stones brought down from the Andes.

A beautiful young girl said to have been buried alive in her coffin…

The narrowest house in Buenos Aires is less than 10 feet wide.

The final resting place of the liberator of Argentina is guarded around the clock by two soldiers.

In the middle of a busy airport, a statue honoring the astronaut who told Houston that Apollo 13 had a problem.