Discovering an unseen urban underworld

Loudoun Castle Theme Park, Scotland
A far less sombre place for exploration is in Galston, Ayrshire. The popular Loudoun Castle Theme Park went out of business in September 2010 after being operational since 1995. Most of its 25 rides remain suspended in time at the park, their paint gradually beginning to chip away. (Video)

Kings Park Psychiatric Center, New York, United States
Abandoned asylums, psychiatric hospitals and hospitals often become sites of urban exploration. It is natural to feel connected with people from the past when you walk through such facilities and stumble upon records and personal effects. On New York’s Long Island, Kings Park Psychiatric Center is a collection of abandoned buildings and structures, including patient accommodation, dining halls, steam tunnels and a cemetery. The centre treated patients from 1885 until 1996. In the “Group 4” patient building, explorers can find paintings and sketches done by patients, presumably as part of their therapy. (Photos)

Paris Catacombs, France
In 2004, Paris police discovered a secret movie theatre inside the city’s infamous catacombs, the underground tunnels where the dead were buried from the late 1700s to the mid-1800s. The purveyors of this cinema were urban explorers who just really loved the catacombs. Appropriately, they refer to themselves as cataphiles. Alongside the remains of six million people, they explore, they throw parties and on certain occasions, they watch movies. Catacomb exploration has such a cult following in Paris that there are special police officers -- known as cataflics -- whose job it is to guard the underground passageways. Travellers seeking a cataphile experience would be well advised to meet up with local groups or guides before heading down. (Audio slideshow)

Odessa Catacombs, Ukraine
Odessa is home to the world’s longest network of underground tunnels. The burial passageways stretch more than 1,500 miles. Created by stone mining when the city was being built, the catacombs have been used over the years as a hiding place for slave traders and as a military base. Today, a portion of this web of corridors has been converted into a museum. Contact the Ukraine tourism board for opening hours, or opt for a private tour. (Photos)