Abandoned Salbert fortifications

Urban exploration (often shortened as UE, urbex and sometimes known as roof-and-tunnel hacking) is the exploration of manmade structures, usually abandoned ruins or hidden components of the manmade environment. Photography and historical interest/documentation are heavily featured in the hobby and it sometimes involves trespassing onto private property.^{[1][failed verification]} Urban exploration is also called draining (a specific form of urban exploration where storm drains or sewers are explored), urban spelunking, urban rock climbing, urban caving, building hacking, or mousing.

The activity presents various risks, including both physical danger and, if done illegally and/or without permission, the possibility of arrest and punishment. Some activities associated with urban exploration violate local or regional laws and certain broadly interpreted anti-terrorism laws, or can be considered trespassing or invasion of privacy.^[2]

Exploration sites

Urban explorers at the entrance of a technical gallery under construction in Paris, France

Abandonments

Ventures into abandoned structures are perhaps the most common example of urban exploration. Many sites are entered first by locals and may have graffiti or other kinds of vandalism, while others are better preserved. Although targets of exploration vary from one country to another, high-profile abandonments include amusement parks, grain elevators, factories, power plants, missile silos, fallout shelters, hospitals, asylums, schools, poor houses, and sanatoriums.

In Japan, abandoned infrastructure is known as haikyo (廃墟) (literally "ruins"), and the term is synonymous with the practice of urban exploration.^[3] Haikyo are particularly common in Japan because of its rapid industrialization (e.g., Hashima Island), damage during World War II, the 1980s real estate bubble, and the 2011 Tōhoku earthquake and tsunami.^[4]

Many explorers find decay of uninhabited space profoundly beautiful, and some are also proficient freelance photographers who document what they see, such as those who document the infrastructure of the former USSR.^[5]

Abandoned sites are also popular among historians, preservationists, architects, archaeologists, industrial archaeologists, and ghost hunters.

Active buildings

Light painting inside an abandoned limestone quarry in France.

Another aspect of urban exploration is the practice of exploring active or in use buildings, which includes gaining access to secured or "member-only" areas, mechanical rooms, roofs, elevator rooms, abandoned floors, and other normally unseen parts of working buildings. The term "infiltration" is often associated with the exploration of active structures. People entering restricted areas may be committing trespass, and civil prosecution may result.

Catacombs

Catacombs (France)

Catacombs such as those found in Paris,^[6] Rome, Odessa, and Naples have been investigated by urban explorers. Some consider the Mines of Paris, comprising many of the tunnels that are not open to public tourism, including the catacombs, the "Holy Grail" due to their extensive nature and history. Explorers of these spaces are known as cataphiles.

Sewers and storm drains

Storm drain outfall in Saint Paul, Minnesota

Entry into storm drains, or "draining", is another common form of urban exploration. Groups devoted to the task have arisen, such as the Cave Clan in Australia. Draining has a specialized set of guidelines, the foremost of which is "When it rains, no drains!", because the dangers of becoming entrapped, washed away, or killed increase dramatically during heavy rainfall.

A small subset of explorers enter sanitary sewers. Sometimes they are the only connection to caves or other subterranean features. Sewers are among the most dangerous locations to explore owing to risk of poisoning by buildups of toxic gas (commonly methane, hydrogen sulfide, or carbon dioxide).

Transit tunnels

Diesel trains in a tunnel of Metro-2 D6 line in Moscow, Russia

Exploring active and abandoned subway and railway tunnels, bores, and stations is often considered trespassing and can result in civil prosecution, due to security concerns. As a result, this type of exploration is rarely publicized. An exception to this is the abandoned subway of Rochester, New York, the only American city with an abandoned subway system that was once operational. The Cincinnati subway is also abandoned, but was never completed. London has a number of stations on the London Underground network that have been closed over the years, with Aldwych tube station a popular location for explorers.

Utility tunnels

Utility tunnel in the center of Zurich, Switzerland

Universities, and other large institutions such as hospitals, often distribute hazardous superheated steam for heating or cooling buildings from a central heating plant. These pipes are generally run through utility tunnels, which are often intended to be accessible solely for the purposes of maintenance. Nevertheless, many of these steam tunnels, especially those on college campuses, have a tradition of exploration by students. This practice was once called "vadding" at the Massachusetts Institute of Technology, but students there now call it roof and tunnel hacking.

Some steam tunnels have dirt floors, poor lighting and temperatures above 45 °C (113 °F). Others have concrete floors, bright light, and more moderate temperatures. Most steam tunnels have large intake fans to bring in fresh air and push the hot air out the back, and these may start without warning. Most active steam tunnels do not contain airborne asbestos, but proper breathing protection may be required for other respiratory hazards. Experienced explorers are very cautious inside active utility tunnels since pipes can spew boiling hot water or steam from leaky valves or pressure relief blow offs. Often there are puddles of muddy water on the floor, making slips and falls a special concern near hot pipes.

Steam tunnels have generally been secured more heavily in recent years, due to their frequent use for carrying communications network backbone cables, increased safety and liability concerns, and perceived risk of use in terrorist activities.

Popularity

The rise in urban exploration's popularity can be attributed to increased media attention. Recent television shows such as Urban Explorers on the Discovery Channel, MTV's Fear, and the Ghost Hunting exploits of The Atlantic Paranormal Society have packaged the hobby for a popular audience. The fictional film After... (2006), a hallucinatory thriller set in Moscow's underground subways, features urban explorers caught up in extreme situations. Talks and exhibits on urban exploration have appeared at the fifth and sixth Hackers on Planet Earth Conference, complementing numerous newspaper articles and interviews.

Another source of popular information is Cities of the Underworld, a documentary series that ran for three seasons on the History Channel starting in 2007. This series roamed around the world, showing little-known underground structures in remote locales, as well as right under the feet of densely packed city-dwellers. Websites for professional and hobby explorers have developed to share tips and locations.^[7]

With the rise in the hobby's popularity, there has been increasing discussion of whether the extra attention has been beneficial.

Safety and legality

A partially collapsed tunnel in the Kyminlinna fortress in Kotka, Finland

Hill 60 bunker. On the right is a corridor leading to the bunker complex and on the left is the "mushroom tunnel".

Urban exploration comes with a number of inherent dangers. For example, storm drains are not designed with human access as their primary use. They can be subject to flash flooding and bad air. There have been a number of deaths in storm water drains, but these are usually during floods, and the victims are normally not urban explorers.^[8]

Many abandoned structures have hazards such as unstable structures, unsafe floors, broken glass, stray voltage, entrapment hazards, or unknown chemicals and other harmful substances (most notably asbestos). Other risks include freely roaming guard dogs and hostile squatters. Some abandoned locations may be heavily guarded by motion detectors and active security patrols, while others are more easily accessible and carry less risk of discovery.^[9]

The activity's growing popularity has resulted in increased attention not just from explorers but also from vandals and law enforcement. The illicit aspects of urban exploring, which may include trespassing and breaking and entering,^[10] have had critical attention in mainstream newspapers.^[11]

In Australia, lawyers for the Roads and Traffic Authority of New South Wales shut down the Sydney Cave Clan's website after they raised concerns that the portal could "risk human safety and threaten the security of its infrastructure".^[11] Another website belonging to the Bangor Explorers Guild was criticized by the Maine State Police for encouraging behavior that "could get someone hurt or killed".^[11] The Toronto Transit Commission has used the Internet to crimp subway tunnel explorations, going as far as to send investigators to various explorers' homes.^[11]

Jeff Chapman, who authored Infiltration, writes that genuine urban explorers "never vandalize, steal or damage anything". The thrill comes from "discovery and a few nice pictures".^[11] Some explorers also request permission for entry in advance.^[12]

Injuries and deaths

Rooftopping

Rooftopping in Hong Kong

Rooftopping and skywalking are the ascent of rooftops, cranes, antennas, smokestacks, etc., usually illegally, to get an adrenaline rush and take selfie photos or videos. Rooftopping is different from skywalking as the latter is mostly about taking panoramic photographs of the scene below and safety (getting home to see and post your photos) is more important than the thrill.^[36] Skywalking has been especially popular in Russia.^[37]

Methods and technology

Some urban explorers use head-cams such as GoPro or other helmet cameras for videos.^[38][39][40]

Some also use quadcopter drones for exploration and recording.^[41][39]

The location-based games Ingress^[42] and the following Pokémon Go^[43][44] based on the former have urban exploration elements. While some are concerned with keeping certain sites secret from the public at large, mainly to prevent vandalism, several apps dedicated to urban exploration exist.^[45][46]

In popular culture

Urban exploration is featured in a number of works, in a variety of media, such as:

Literature

• Garrett, Bradley L. (2013). Explore Everything: Place-hacking the City. Verso Books. ISBN 978-1-78168-129-9.^[47][48]
• John Green's novel Paper Towns (2008)
• James Rollins' Sigma Force novel 6.5, The Skeleton Key (2010)

Television

• Red Bull TV launched URBEX – Enter At Your Own Risk on 1 August 2016, an 8-part series about the motivations, mindsets, and adventures of urban explorers.
• Travel Channel aired Off Limits (2011–2013), a series based on urban exploration hosted by Don Wildman.
• Unforgettable's "Maps and Legends" (season 2, episode 7) featured urban exploration.
• SKAM France (season 6) featured urban exploration^{[citation needed]}