This house's itty bitty size means no humans allowed.

Hundreds of glow-in-the-dark objects light up a museum in a historic zinc mine.

One of the largest underground systems runs under Canada's largest urban center.

This unusual structure may be on its way to becoming a cultural landmark in Toronto.

Willy Wonka would love this weird half-a-home.

The vaulted ceiling is home to a scurry of “squirrelgoyles.”

The pretty iron lamp is a reminder of the architecture underneath London's streets.

In 2013, historians discovered a hidden room devoted to the art of making royals' hot chocolate.

Seven mini rowhouses fill the gap between 54 and 70 Westerstraat.

This unique bridge curls up like a caterpillar to let boats pass and then unfurls again to span a small canal.

Buildings from the fictional planet of Tatooine still litter the Tunisian desert.

Spanish architects used seized Muslim gravestones to rebuild parts of the fortress.

Claude Monet immortalized this medieval bridge in two of his paintings.

This overlooked street light once served as a KGB dead letter box.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

Unique antiquarian shop specializing in globes, maps, and prints.

The iconic boulevard is the perfect place to catch sight of a bicycling skeleton, a levitating Satan, or a chef with his head stuck in a pizza.

The largest crypt ever constructed in France was built in the 11th century on an ancient Druid sacred site.

A hidden three-foot-wide house separates these two regal churches.