This medieval manor house was equipped with secret compartments for hiding priests.

A rare surviving Victorian greenhouse designed specifically to house giant water lilies.

A hidden bathhouse in one of Stockholm's oldest and busiest neighborhoods is open to anyone who can find it.

Dine on food tied to Viking history and legend at this subterranean Stockholm spot.

An illuminated manuscript comprising the life's work of a lone monk, inexplicably decorated with a portrait of Satan himself.

Built in the 1300s, this magnificent building that hosted England's kings and queens transports you to the Middle Ages.

A preserved block of timber buildings from the city's industrial era in the Middle Ages.

This ruin in a suburban park may be the place where Shakespeare's "A Midsummer Night's Dream" was first performed.

This amazing 15th-century mural remained hidden in plain sight for centuries.