This Arizona observatory is famous for investigations into Martian life, and as the place humans first spotted Pluto.

Ancient pueblos built into the base of a natural canyon wall.

The artist James Turrell is repurposing an extinct volcano crater as an observatory to experience the cosmos.

A stealthy Apache hideaway that became the haunting site of a mass grave.

This 4,000-foot-diameter hole is touted as "the most well known, best preserved meteorite crater on Earth."

This public square capitalized on a single Eagles reference to bring some life back to an Arizona town.

This sanguine boulevard was named after a deadly cowboy bar fight.

The curios of pharmacist and collector Henry Wellcome.

Bronze sculpture celebrating the relationship between Churchill and Roosevelt.

Museum dedicated to the UK's first charity for abandoned children, with keepsakes of the mothers who left them behind.

The breadfruit-adorned final resting place of the infamous Captain of the HMS Bounty.

Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

Hear the quietest sound from across the dome.

Public access to clean drinking water was an instant hit among the masses.

Dictionary Johnson’s favorite feline.

The anatomical-pathological collection of a man who changed surgery.

An unusual round church in London with a Templar past.

A cluttered and astounding collection of antiquities and curiosities.

London's smallest police station is barely the size of a phone booth.

One part local history, 99 parts gruesome haunted house.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

A small "palace" and museum made of, and devoted entirely, to salt.

Park filled with machinery that drove the southern agriculture and oil industries forward.