This impressive working clock made of 16,000 plants changes its flowers twice a year.

A natural gas leak provides a flickering flame beneath a waterfall.

A tree full of wishes and footwear.

The birthplace of America's favorite fruit-flavored mystery dessert.

The “American Gothic" artist's largest works hang in an Iowa State University library.

Send a postcard while vacationing with Satan.

Legend tells how a Spanish soldier disappeared from this isolated sentry box without a trace.

This colorful gate stands as an entrance to the walled city of Old San Juan.

This bleach-white graveyard overlooking the ocean is accessed through a tunnel.

An imposing statue of the first prime minister of Antigua and Barbuda stands in the middle of a traffic intersection.

This popular tourist cave was ignored for almost 200 years before being mined into an attraction.

An abandoned colonial French prison notorious for its hellish conditions.

This striking, two-toned confluence of rivers is visible from space.

A beautiful opera house in the heart of Amazonia has recently restarted performances after a 90-year hiatus.

This incredibly diverse research station is one of the largest tropical botanical gardens in the world.

A crumbling cathedral condemned by an earthquake.

Legend says this sacred tree was a gift from goddess Athena.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

This historic electric train has operated with regularity since the early 1900s.

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Construction of Barcelona’s iconic (but controversial) church was finally completed in 2026—a century after the death of its architect.

The oldest giants in Catalonia are now displayed in a 14th-century Gothic church.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

The marker offers a rare chance to be in four U.S. states at once, though there's some controversy over its geographic accuracy.