Places kaiaoverthemoon Wants to Go

This vast, water-filled underground labyrinth can only be toured by boat.

A galaxy of glowworms—larvae of a gnat—hides deep in the belly of these caves.

This army of concretions is an unexplained geological phenomenon unlike anything else in the world.

Along the most northwestern point in Africa is an ancient cave surrounded by legends.

The sunlight passing through the opening of this huge cave system creates a magical effect.

These otherworldly caverns form Earth's oldest known cave system.

At the right time of day, sunlight floods through the roof of this cave and illuminates the small pavilion hidden within.

Perhaps the most spectacular grotto along the Algarve coastline.

Peek into a cave of giant, glimmering crystals.

The ceiling of this cavern is dripping with multicolored marble stalactites.

This ancient limestone cave system contains many impressive geological features.

One of few vertical lava tubes in the world accessible by foot.

The spectacular geological formations make it one of the most impressive caves in Europe.

A subterranean playground in an abandoned slate mine.

Legend has it these caves were created by a deity called Ogba, who is said to live inside the winding subterranean caverns.

Tubing through a cave lit with glowworms is a magical underground experience.

Berthed at the Charlestown Navy Yard in Boston, "Old Ironsides" is the oldest commissioned warship still afloat.

On a former island, this old fortification once used to protect the Boston Area and started Edgar Allan Poe in his military career.

A luxury hotel constructed out of a former jail.

An enormous, inside-out glass globe built in 1935.

Two thousand artifacts from around the world collected by one woman who loved to travel.

One of the oldest used bookstores in the U.S. has been selling antiquarian treasures since 1825.

Line up for a hickory-smoked BBQ bologna sandwich at this family-run institution.

This third-generation institution is one of the last in London that still cures its own salt beef for epic sandwiches.