The world's brightest bioluminescent bay.

A floating underwater hotel, created by a Swedish artist.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

A hands-off space for graffiti artists to hone and display their skills.

Rare and wonderfully wormy cadaver art captured in brass for centuries.

One of the oldest libraries in England, and one of the last of the great medieval chained collections.

On a site with a long military history, a 1980s shelter.

A hundred copies of Antony Gormley's naked body stare out across the water.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

A vortex fountain that seems to rise out of the ground.

A church that bred legends, and served as an inspiration for the Da Vinci Code.

Built during the Scottish boom in the oil industry, the village was never inhabited.

A book bound in the skin of an infamous criminal, along with countless other specimens.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

360° views of the city plus five floors of optical illusions and hands-on science.

One of the oldest scientific gardens in Britain, containing more than 13,302 plant species in its core collection.

A 200-year-old collection of oddities and medical paraphernalia.

Giant stone letters dedicated to the founder of Armenia's alphabet.

Yale University's home for rare works, including the mysterious Voynich Manuscript.

Stroll through a wonderland of stupendous moss-covered trees.

The abandoned village of Skarð aptly illustrates the idiom "Don't put all your eggs in one basket."

Spring that emits water and fire at the same time is said to have remedial properties, and sparked its own religion.

A mysterious light floating in the trees of Arkansas may be a piezoelectric effect.