Germany’s “treasure chamber” is located in a disused mine near Freiburg. Documents from over a thousand years of history are stored in the underground archive.
A bridge which connects Hong Kong with Macau and Zhuhai, is the world’s longest sea crossing.
In 1959 it was the centre of project Military Atomic Energy Authority operation orpheus investigating the possibility of masking the seismic signal given out by underground nuclear tests.
That tiny orange figure levitating above this futuristic structure high on the Songshan mountain in rural Henan, China, is indeed a monk.
About twenty kilometers from the city of Boulogne-sur-Mer, near the hamlet of Mimoyecques, in northern France, lies a once-secret underground Nazi base.
The Superconducting Super Collider (SSC) (also nicknamed the Desertron) was a particle accelerator complex under construction in the vicinity of Waxahachie, Texas.
Located in the city of Kitakyushu, Japan, Kawachi Fuji Garden is home to an incredible 150 Wisteria flowering plants spanning 20 different species.
The Post Office Railway, known as Mail Rail since 1987, is a driverless underground railway that was built to move mail between sorting offices.
The Kelvedon Hatch Secret Nuclear Bunker at Kelvedon Hatch, in the Borough of Brentwood in the English county of Essex, is a large underground bunker maintained during the cold war as a potential regional government headquarters.
Five meters below the runway of Sarajevo’s airport runs a short stretch of tunnel that was dug out during the Siege of Sarajevo to bring supplies to the cut-off city. For four years this 800-meter long tunnel was the besieged city’s only connection to the outside world, and its life support.
The Tunnel of Love enjoys a worldwide reputation. It is known to be one of the nicest sections of railway and one of the most romantic places in the world.