Things roll uphill on this Mexican street that seems to defy gravity.

Frida Kahlo's childhood home, now a museum of her life and works.

This incredible college library is a visual masterpiece of mosaic art. It also looks kind of like a giant boombox.

The famous artist couple lived and worked here, in two different houses separated by a bridge.

66,000 pieces of art, donated by one of the world's richest men.

Diego Rivera's massive tiled fountain and failed infrastructure project.

The only castle in North America to ever house European sovereigns.

A jewel of the Mexico city skyline now slowly crumbles after surviving an earthquake.

A jaw-dropping "megalibrary" that turns book-browsing into a geometric adventure.

Gilded heaven for philatelists and architecture freaks, still in full working order despite sitting atop tremulous ground.

It took over 100 years to decode this enigmatic epitaph for two buried brides.

The nude sculpture on this fountain shocked conservative townsfolk when it was first unveiled, but not as much as the dead body found in it decades later.

Genesis of modern hydroelectric power.

Soaring over the Niagara Whirlpool since 1916.

This seemingly cursed monument is dedicated to one of Canada's great war heroes.

This mill on Lake Erie appears to shrink as a viewer approaches thanks to an optical illusion.

Legend says that this short Canadian tunnel still holds the dying screams of a girl who burned alive.

The roadway bend where highway painters practice their craft looks like expressionist art.

This "Palace of Purification" has made many film appearances as a dark and sinister headquarters.

The third version of this tall sailing ship sits, rusted and burnt, in Lake Ontario.

Lost subway station nestled beneath Toronto's busy commuter line.

The statue of the famous elephant who was the original source of the word "jumbo".

These strikingly barren, rolling red hills were caused by bad farming practices.

With well over 130 falls and cascades to brag about, Hamilton, Ontario has earned its stripes as the waterfall capital of the world.