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

Within the church are the relics of the martyrs St. Jean de Brébeuf, St. Gabriel Lalemant, and St. Charles Garnier.

Eighty million natural history specimens call this gargantuan museum home.

The first geometric self-supporting spiral stairs in Britain are a truly beautiful sight.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

The rose garden in Regent's Park where Pongo and Perdita met for the first time in Disney's "101 Dalmatians."

Metal horses galloping through a London fountain provide a link to the city's past.

The Tudor-style cottage in the middle of the square is not quite what it seems.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

Before there were doorbells this bronze ear was installed for visitors to announce their arrival.

This small Milan street is filled with colorful homes and a rich history.

Artistic tombs, monuments, and a beautiful "Hall of Fame" lurk inside this cemetery.

This historic hotel preserves many treasures from its heyday hosting passengers on the Orient Express.

One of the largest wooden constructions in Europe was meant to be a casino, but soon became an orphanage.

Over the centuries, this island paradise has done it all, from providing monks with ecclesiastical respite to sheltering an exiled Leon Trotsky.

A marvel of Byzantine engineering under the streets of Istanbul.

Legend says if you stick your thumb in the hole and it gets wet, your wish will be granted.

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

This shuttered power plant is now Turkey's first industrial archaeology museum.

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.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

In this breathtaking canyon, crocodiles bask on boulders and glide through the murky waters.