Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

Jesus' footprints and the first catacombs in the world.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

2300-year-old Roman road connecting the empire.

A museum devoted to bringing to light forgotten or neglected histories through exhibitions, education and public programming.

The world’s oldest and biggest bookstore stocking only mystery, crime fiction, espionage, and thrillers.

Historic town settled in the 19th century because of its convenient location along a popular coal transport route.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

A pride of the state, this working museum crafts pottery mosaics in the style of Pennsylvania's earliest European settlers.

A giant light 13 feet high shines near Thomas Edison's old Menlo Park lab.

Nassau Hall has served as army barracks, a museum, and played a key role in the American Revolution.

A historic town sits upon the site of a long-lost 18th-century trading community.

One of the world's largest model railroads is a mind-boggling achievement.

This ancient market is often referred to as the oldest shopping mall in the world.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."