The Giant Lemon of Lemon Grove.

The world’s oldest active sailing ship.

The classic Atari game's iconic aliens have invaded downtown San Diego.

The tiniest tiki room in San Diego.

Not truly a ship nor a building, the Navy's first and last "landship" is now abandoned due to clerical issues.

Go deep on these fascinating fish, and get a bonus lesson on the importance of marine conservation.

This massive redwood tree has stood in Northern California for nearly 2,000 years.

Most prolific publishing house in the 1600s open to the public.

A Dutch passageway's artistic, aquatic-themed makeover pays tribute to the capital city's famed waterways.

Western Europe's only representation of a Roman goddess still in its original location sits in an unassuming park.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

Guns that have been defending San Francisco since 1904.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Built for an exposition in 1915, these horticultural displays have stood the test of time.

One of the largest trees of its kind in California.

World's largest collection of serial killer artwork and other macabre exhibits.

Created by one of England's most prolific labyrinth designers, inspired by Bath city history.

This picturesque horseshoe weir was first built in the 1600s to prevent flooding in the town of Bath.

This astronomical clock is the second oldest in England.

The oldest residential street in Europe also features an optical illusion.

Fascinating town where normal life interfaces with the occult.

This hill and tower are steeped in legend, from King Arthur to the Holy Grail.

One of the oldest and certainly best preserved Cistercian abbeys still in existence.

A naturally mummified 2,000-year-old man.