A spectacular Petrine Baroque summer palace commissioned for Catherine I by Peter the Great.

The first designer power line in Estonia.

The widest natural waterfall in Estonia is a sight to see in all seasons.

This Estonian watchtower looks like a big tree with two giant bird nests on it, complete with a "golden egg."

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

An ancient necropolis of magnificent tombs.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

The oldest university museum west of the Mississippi retains its 19th century feel.

Iconic red and white plaques show the creative names invented to navigate the city streets.

Its sunny hues are believed to have inspired the town's color palette.

Found down a long dirt road, a sacred Mexican cenote and 18th-century hacienda remain hidden.

If you can look past the nearby sewer pipes, this urban sinkhole grotto is a mini-paradise.

The famous author's birthplace is preserved in a town that he once described as narrow-minded.

Take a hidden path to the mouth of the cave to watch millions of bats swarm at sunset.

For the last century, this international border within a small town has appeared and disappeared various times.

This striking memorial is one of Estonia’s most controversial Soviet leftovers.

A forest park outside Tallinn full of architectural and artistic curiosities.

The legendary giant's severed hand sits on Antwerp's popular shopping street.

Tintin's creator is celebrated in an immersive museum that's an astounding work of modern art.

This small corner bar is home to a rare 1930s dance organ that still plays tunes for one Euro.

A man throwing a giant severed hand towers over Antwerp’s main square.

This bike path traverses the treetops.

To enter this cluttered-yet-cozy sanctum of Belgian brews, ring the bell and tell the gatekeepers you've come “to taste beer.”