Started as a kitchen garden, now the second largest botanical garden in the world.

The fairy tale castle of the "fairy-tale king."

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

Every color in the rainbow awaits.

The magical, mossy forest that inspired Princess Mononoke.

Experience park where visitors are told to expect the unexpected.

Hot springs monkey spa in the middle of Hell's Valley.

The ominously named cave is home to some remarkable ancient art.

Legends of treasure and spirits flow from this this fairy tale-like oasis.

One of Amsterdam's narrowest houses is located right across the canal from its widest.

Seven mini rowhouses fill the gap between 54 and 70 Westerstraat.

This unattributed sculpture in Amsterdam is hiding in plain sight.

An ancient passage filled with stalls selling used books, once frequented by Vincent Van Gogh.

This gorgeous reading room houses the oldest and largest art history library in the Netherlands.

Established in 1638 to battle the Black Death, Hortus Botanicus Amsterdam is a treasure trove of rare flora.

Living trees form the structure of an open-air palace.

A stairway to heaven, or to nowhere at all.

This beautiful ridge-top trail is dotted by tiny homes apparently built by a group of itinerant fairies.