Colorful concentric circles honor a small Croatian town's supposed spot at the nucleus of it all.

Trimmed trees grow alongside the graves like topiary tombstones.

The labyrinthine home of the National Archives of Estonia is an experimental blend of architecture, art, and history.

This peculiar border irregularity is the only way to legally enter Russia without a visa.

Tiny memorials honor individual victims of the Holocaust.

A monument to the man who almost killed Hitler.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

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

The pyramid and dome deep inside the Dzūkija forest are believed to channel divine energy.

A field filled with carved medieval tombstones called stećak.

The world's oldest grape-producing vine has survived four centuries of turmoil and even has its own anthem.

The anatomical-pathological collection of a man who changed surgery.

Murals of the wild parties once held on the frozen River Thames.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

The pioneer of psychoanalysis spent the final year of his life here, still seeing patients on that famous couch.

Installed at a chaotic intersection, this gave London traffic cops a place to hang their heavy woolen coats.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

London's smallest police station is barely the size of a phone booth.

A cluttered and astounding collection of antiquities and curiosities.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A student driver's nightmare.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

The signs of a long buried road can still be found hidden beneath a London sewer grate.