The widest natural waterfall in Estonia is a sight to see in all seasons.

This Soviet-era "closed town" was a top secret uranium producer often left off of maps.

Disused seaplane hangar gets a second life as the jaw-dropping home of Estonia's museum of maritime history.

This disappearing geyser has been attributed to witchcraft, but really it's all about rainfall.

Mysterious craters may have been home to an ancient cult.

For the last century, this international border within a small town has appeared and disappeared various times.

This ducal residence was once home to a future Russian empress and a French king in exile.

A unique museum dedicated to the famed Soviet director and other cinema greats.

This former Nazi labor camp is now a poignant memorial, complete with giant Soviet-style monuments.

These abandoned vessels are destined to be reclaimed by the forest.

This ornate church has survived Nazi and Soviet occupation, including a short stint as a Soviet-era gymnasium and cinema.

This celebration of Latvia’s freedom and independence avoided demolition over half a century of Soviet occupation.

This abandoned beacon is moving closer and closer to the sea.

Stockholm's deepest subway station is also a stunning ecological wonder.

It houses the remains of a 17th-century version of the Titanic.

Stockholm's decidedly unique public transit system has doubled as the world's longest art gallery for decades.

The discovery of an old wall led to the creation of this fascinating museum about the city in the Middle Ages.

Sweden's first electric elevator remains hidden within a fortress-like building.

Stockholm's last remaining paternoster elevator.

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

Although rarely used, there is still a hidden room for the royal family at the Stockholm central station.

This homeless brass fox tugs at your heartstrings from the foot of a Stockholm bridge.

This behemoth bovine guards an Estonian town and is a memorial to the lost species.

A trio of giant wooden megaphones turn up nature's volume in this Estonian forest.