Romania's triumphal arch looks out over Bucharest.

This bone-filled cave got its name after they found 140 bear skeletons inside.

This communist behemoth is the heaviest building in the world and a legacy of a brutal regime.

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

Some call this eerie forest of crooked trees the "Bermuda Triangle of Romania."

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

Moss and stone turn this waterfall into an otherworldly liquid veil.

When zealous marijuana enthusiasts kept stealing the "Mile 420" highway marker, the State of Colorado got creative.

The 7,000-foot finish line of America’s first Olympic Trials marathon.

This Colorado fire station has been in continuous operation for more than a century.

A long and winding trail through history led to the current iteration of this mountaintop tower.

On the edge of grassland in northeastern Colorado, these rock formations are some of the few remnants of a high plain that has eroded away over millions of years.

Ute tour guides have been sharing the ancient dwellings and rock art inside this large park with visitors for more than 40 years.

The temporary burial site of the man who shot and killed Jesse James.

This remote Colorado canyon is home to the second-largest collection of natural arches in the world.

A dangerous narrow-gauge railroad once traced a route through this striking canyon.

A memorial dedicated to the victims of the Columbine High School shootings.

The site of the gruesome massacre—and maybe cannibalism—of five men, a tragedy that made Alferd Packer infamous.

Two tall rocks sit at the center of this site, once the home of a large Ancestral Puebloan community.

This enigmatic building features numerous architectural styles.

The final resting spot of the Colorado Transportation Department's beloved unofficial mascot.