Area 51 was built in 1940. Before that, it served as an animal sanctuary. In 1942, the U.S. Government War Department restricted it from public access. It is located in Lincoln county, southern Nevada and is about 4,531 square miles. It is a part of Edwards Air Force base, even though they are in different states. The government's official name for Area 51 is the Nevada Test and Training Range at Groom Lake. Among its unofficial names are Homey Airport, Groom Lake, Paradise Ranch, and Dreamland.
The facility has many uses. According to the government, all of those uses pertain to training. It has served as an aerial gunnery, bombing test site, nuclear test site, proving ground, flight test area, blue flag exercise area, green flag exercise area, and red flag exercise area. Basically, this means that troops from other branches of the military are brought in and trained along with the Air Force personnel in realistic combat conditions.
The first reports of UFOs around the area began in 1955, which was around the same time the U-2 CIA planes were being tested. At the time, commercial airlines only flew up to 20,000 feet, while the military only flew up to 40,000 feet. The U-2 flew up to 60,000 feet. This caused a huge influx of UFO sightings by pilots who were not privy to the project. Because of this influx of UFO sightings, the government started Project Blue Book, even though they knew the U-2 was causing the majority of reports. They could not, however, tell the public, since this was top secret information.
The U-2 CIA planes were made so that the U.S. could fly over the Soviet Union in order to spy on their weapons. Since the planes flew at 60,000 feet, they generally could not be detected by Soviet technology. The mission was a success, although at least one U-2 plane was shot down over the Soviet Union.
The military denied the existence of Area 51 until 2013. In 2005, Dr. Jeffrey T. Richardson filed a Freedom of Information Act petition regarding the U-2 Lockheed, which prompted the government to release information regarding Area 51. In the report, it explained that the facility was used for training purposes. No mention of aliens was in the document, although many to this day believe that the facility keeps aliens locked away in cells.
Area 51 employs a large number of civilians. They generally live in the areas around the site and are bused into the facility every Monday. They stay there until Friday, when they are bused home. The vans that are used to transport these civilians are highly monitored and protected.
Security around Area 51 is historically tight. It is protected by so called camo guys, who generally patrol the area in white trucks. Although deadly force is not their first option, they do carry M-16s and are instructed to utilize them if necessary. Generally, if you are caught getting too close to Area 51, the camo guys confront you and call the police. You are then issued a $600 ticket and either detained or forced to leave the area.