A constellation of golden cobblestones shows the names of local children born under a full moon.

Amsterdam's former hotspot for public executions and dissections.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

Three connected pink triangles memorialize persecuted gays and lesbians throughout history.

This museum housed in a former brothel explores the past and present of sex work in Amsterdam.

Museum preserving torture methods from the past.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

A seaside castle complex that stood through centuries of conquests.

The ruins of this monumental city founded by the first Roman Emperor are strangely overlooked by most travelers.

This knockout museum lies in a sleepy corner of London.

An architectural oddity hides in plain sight on this iconic London bridge.

This unassuming building produced some of the world's most famous bells.

The bronze uniforms commemorate the vital role of women during World War II.

From lefty Jewish gathering site to hip cultural site in just 80 years.

City law dictates that this mountaintop cathedral containing the heart of a saint is to remain the tallest building in town.

Every year, the colorful murals of Montreal get a complete makeover.

The skyline of Montreal includes the silhouette of an unexpected fruit-shaped Canadian staple.

A Montreal deli that was so beloved that it was allowed to circumvent their laws of language.

Montreal's giant farmer's market is a foodie's best friend, especially in the winter months.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

This 1967 experiment in modular architecture was designed to be a new model for urban living.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

The 28,000-year-old specimen is remarkably intact.

The remains of Martha, the last known passenger pigeon, serve as a tool to educate about conservation.