Paranormal activity on the great lakes.

One of Frank Lloyd Wright's final works was this UFO church.

A large circus museum with summer performances.

This striking art museum holds an amazing series of curiosity cabinets.

The arboretum whose marshy soil sucked up the dreams of housing developers.

More than 5,000 contemporary and "historic" mustards from around the world.

This cave holds a surprisingly colorful variety of geological oddities.

These Great Lakes sea caves accessible by boat in the summer turn into temples of ice reachable by foot in the winter.

A bizarre house filled with an astounding array of collections.

A former imperial sea-fortress and Soviet prison.

An abandoned textile factory on the "island of crows" was home to Estonia's first workers' strike.

Historic slum of Tartu.

This stoic bronze soldier stands as a symbol of Russian sacrifice or Soviet oppression, or maybe both.

A historic scientific breakthrough that crosses nine borders.

The Guardian of Tallinn.

First point in the Struve Geodetic Arc, a 19th century undertaking to measure the Earth's size and shape.

This dizzying tower was built to better broadcast the 1980 Moscow Olympics.

Estonia's largest creative city is a vibrant bohemian hub located within a former industrial complex.

This old Estonian mine has been kept like a sprawling time capsule of the local shale industry.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

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

Once standing on solid ground, this slender beacon is a victim of the very shoreline it was charged with announcing.

Man-made mineral caves house massive bat colony.

A decommissioned submarine base makes a great space for graffiti art.