An abandoned coal mine reached by a steep hike.

One of the few surviving examples of the first lock and dam system built on the Ohio River.

A psychedelic labyrinth on the San Francisco bay.

The oldest family-run luncheonette in New York, last renovated in 1948, still serves food and drinks the old-fashioned way.

A tiny museum housed in a New York freight elevator specializes in the "overlooked, dismissed, or ignored."

A crumbling hospital from the 1850s on Roosevelt Island.

The world's newest astronomical clock is also its most accurate.

No one knows the origin of this creepy little stone man with an oversized phallus.

Pay your respects to a country that only existed for a few weeks.

Also known as the Blue Church, the building was consecrated to the daughter of Andrew II.

An unconventional memorial to the women burned as witches in Bratislava.

This statue points to another unusual companion work of art often overlooked by visitors.

Dedicated to a synagogue that was destroyed after having survived World War II.

According to the local legend, these boys and ducks were turned to stone by an angered water goblin.

A relic of the Cold War tucked away in the forested hills above Bratislava.

The inverted pyramid design of this station stands out amid Bratislava's urban landscape.

A perfectly preserved hill village where the buildings are painted like white lace.

The blood-soaked ruins of the castle where the murderous Blood Countess was walled in alive.

A diminutive statue that was inspired by the sculptor's own daughter.

This was once the largest city in Kazakhstan, and a major stop on the Silk Road.

Iconic pyramid from famed British architect Norman Foster designed to represent all of the world's religious faiths.

An abandoned Soviet-era mining town in the mountains of South Kazakhstan.

Student protesters used these bells as symbols of defiance in the early 1970s.

A 10-foot segment of the concrete barrier stands quietly on the campus.