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

This city square is home to Amsterdam's oldest church and a statue honoring Dutch sex workers.

A beautifully eclectic mix of architectural styles.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

The attic of a four-century-old canal house hides a clandestine church.

The history and future of cannabis.

This historic Amsterdam bar used to accept sailor's monkeys as payment.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

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

Rumored to have been frequented by Vincent van Gogh, it's the only remaining genever producer in the Hague.

Strange secondhand shop showcasing taxidermy and oddies

Only a few walls remain of the last church the Pilgrims used before they sailed to North America.

The remnants of a WWI naval mine that once terrorized the country now decorates a street.

This century-old street sign is a forgotten remnant of the old city.

A retail shop has preserved the 17th-century food cellar from the old building it now occupies.

The remains of a medieval wall discovered in the basement of a jewelry store.

This public toilet built in the famous Amsterdam School architectural style is a Dutch national monument.

An unassuming rod in the Netherlands was once the old standard unit of length for the entire Dutch empire.

This 11th-century castle sits so low you can't see it behind the surrounding buildings.

A trio of red, white, and blue stones embedded in the streets of Leiden are markers of medieval territory and law.

One of the Leiden's oldest pubs is also the birthplace of the Heineken star.

This Dutch art piece became a Russian icon.

The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.

Science meets wall art to highlight the beauty of famous mathematical equations.