The rotting skeleton of a shoreside fun fair that was destroyed by fire and storms still haunts the Brighton ocean view.

The final resting place of many of Germany's most famous communists.

This water-tower-turned-high-end-apartment building was once the site of an early Nazi concentration camp.

From Iggy Pop to David Bowie to Nick Cave, this regal music studio has served some of the all time greats.

The music is over at the Ballhaus Riviera Ballroom, but the ballroom remains in haunting disrepair.

This classic restaurant features a gorgeous mirror-clad room.

This futuristic German spa allows visitors to float in a pool of salt water while zoning out to underwater techno.

The floorboard scrawling of a tragic madman is on public display outside a Paris hospital, much to the dismay of its opponents.

Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

A subterranean shelter remains intact under a busy Paris railway station.

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

A lone cannonball remains lodged in the walls of the Hotel de Sens as a sober reminder of a revolution.

The largest medical and anatomical collection in France lies hidden from the public.

The curious underground history of keeping Paris clean.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

This museum houses an imposing skeleton army comprised of creatures great and small.

Indents in the pavement are all that remain from a grisly death machine in Paris.

Egyptian Revival movie palace abandoned for decades and restored in 2013.

Stroll through retro Paris while shopping for old postcards and discarded doll heads.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

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

Since 1874, this macabre collection has developed into a museum devoted to Scotland Yard's mementos of dastardly deeds.

The "shampooer of kings" who opened London's first curry cafe was a celebrity in the 19th century, but is all but forgotten now.