Smallest house in Toronto sits on a lot meant to be just wide enough for cars to drive through.

This museum promotes informed contraception by documenting its often secret past.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Built to give thanks for the passing of a plague epidemic, this cathedral is a one-of-a-kind architectural hybrid.

A neo-Gothic church built to thank God for saving the Emperor of Austria from an assassination.

300 years of pharmaceutical history on display.

This snug medieval lane is one of the narrowest streets in the world.

An industrial site turned into Hungary's most cherished natural wonder.

A German apartment building hosting as many trees as human occupants.

Cross mysteriously appeared for 36 years.

"Medieval" castle built in the mid-20th century by one family.

Fantastic stories on a miniature railroad.

Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

The world's oldest known salt mine.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.

Swarovski's museum/theme park is a fake diamond fantasia overlooked by a giant.

The townhouse where the "Blood Countess" Elizabeth Báthory started her murderous career.

The shell of a medieval fortress offers commanding views of the area it once protected.

American soldiers discovered Europe's best one-liner at the end of World War II.

The prototype for all Nazi concentration camps.

The prison where Hitler wrote "Mein Kampf," and 278 Nazis were later executed for war crimes.

Daily jousts and dancing barrel makers in Munich's mechanical clock.

These bronze pamphlets remember a remarkable group of Germans who fearlessly opposed the Nazis in the very center of their power.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.