Deadliest lake in the world suffocated over 1,746 people in one night.

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

Medicinal spa created with the discharge from a geothermal energy plant.

A student driver's nightmare.

The largest of London's subterranean rivers and once a mad, bad center of London life.

Charles Babbage's proto-computer, painstakingly brought to life.

An unusual round church in London with a Templar past.

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

Bronze sculpture celebrating the relationship between Churchill and Roosevelt.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

A friendly pub with a sordid past in cock fighting.

This small collection of rare books was uniquely locked up for safe keeping.

High-end antique collection housed in a centuries-old church.

Hidden beneath the streets of London is a secret subway that only carried mail.

A good place to research the Freemasons, esoterica, occultism, and hermeticism.

This former Masonic lodge has been transformed into part museum, part bar, all awesome.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

The British monarchy's stamp collection is one of the most impressive in all of Europe revealing generations of royal nerdery.

The only theatre in the world constructed specifically for sound movement.

This shop specializes in oddities and Victorian-inspired wonders.

A working model of the entire San Francisco Bay and much of the Sacramento River Delta, complete with regular tides that change every 14 minutes.

A winding path built in secret on the edge of the continent.

The restored and active Victorian-era final resting place of San Francisco.