A seemingly out-of-place comic book surprise sits on the 21st floor of the tallest university library in the world. 

Smack-dab in Campania’s volcanic fields, this scenic lake was once thought to be the gate of hell.

This lesser-visited World Heritage site in Athens boasts an impressive ensemble of medieval gold mosaics.

A small but very fascinating fountain in the center of Rome with four books and a deer carved.

This lonesome Monterey cypress has survived centuries of wind, salt, and at least one attempt at arson.

Wander the sprawling living museum on the site of one of a 16th-century community.

Ancient Phoenician and Roman tombs carved into the rock overlook the Moroccan coastline.

These abundant, over-the-top monuments are so widely scattered that they define the entire compact capital cityscape, often leading to jokes about whether there are more statues than residents.

Eat the ultimate iteration of Portugal's most beloved pastry.

The train collection of an eccentric New England seafood mogul is now a National Historical Site.

The world's largest collection of historic U.S. military naval vessels.

This vintage short line in Amish country runs passenger steam train excursions and still hauls freight.

One of the first amphibian migration tunnels in the United States encourages a tradition that has inspired Amherst residents for decades.

View the ancient remains of buildings and the ancient "River of Hades" before hopping on a train.

Gladiators once walked this ancient, subterranean passage.

A preserved trolley track that was transformed into a museum of transportation.

One of the oldest family businesses in Reykjavík serves lamb-based hot dogs.

Dedicated to the man who created the first radio wave communication system.

This fishing contraption sits on top of a series of spindly wooden stilts.

This monastery set over a holy cave contains the oldest known painting of Saint Francis of Assisi.

The ancient Greeks abandoned this quarry to escape Hannibal's devastating invasion.

The home of an antique carousel still in operation.

The phrase "the shot heard around the world" was coined after a skirmish at this bridge.

This extinct volcano rises above Edinburgh and is special for its panoramic views over the city.