Formerly Yugoslavia's "forbidden island," this sleepy little city still holds the abandoned remains of military strongholds.

An ethereal glowing blue ocean cave in Croatia.

Longest fortress system anywhere in Europe.

Picturesque basketball courts sheltered by historical defensive walls and with an enviable sea view.

Remote and wild, Kinnarodden is the northernmost point of mainland Europe.

At the very tippity-top of Europe is a cliff from which you can view the midnight sun.

This one-room museum is dedicated to Norwegian history and jokes.

At this Arctic outpost, get to know members of the indigenous Sámi community and meet their herds.

This functioning parish church is also the site of many concert performances due to its wonderful acoustics.

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.

A simple but powerful tribute to the 20 victims of the 1692 witch trials.

The only structure left with direct ties to the Salem witchcraft trials of 1692.

The de facto symbol of Copenhagen is this bronze fairytale which cannot seem to keep its head for very long.

This bridge's unique architecture honors nautical heritage and encourages self-awareness.

Danish tourist destination well known for open stalls where vendors sell marijuana on the street.

Climb to the top of its spiral spire for spectacular views of Copenhagen.

A raised boardwalk winds through a thicket of stunted, century-old trees no more than nine feet tall.

California's own majestic geyser is powered by a subterranean volcano.

A sculpture dedicated to Napa Valley's oldest mineral water company.

California's own medieval Italian castle, authentic down to the 300-year-old iron maiden in the dungeon.

San Francisco's newly reopened hands-on science museum.

A collection of 20th-century automata, penny arcade games, and musical contraptions.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

Concrete strongholds stand guard over the Golden Gate.