Before 9/11, airport security was far more relaxed than it is today.
Friends and family could accompany travelers through security without a boarding pass. Knives and blades were allowed in carry-on bags as long as they were smaller than 4 inches. Private companies, not the government-run Transportation Security Administration, handled screenings.
Airport security did evolve over the decades in response to bombings — like the Pan Am bombing over Lockerbie, Scotland, in 1988 — as well as hijackings and other threats. X-ray machines and metal detectors slowly became familiar features, but the experience was vastly different compared to modern air travel.
In the aftermath of September 11, airport security transformed almost overnight. These vintage photos show how travelers once navigated a system that now seems unrecognizable.
Before 9/11, checked luggage was not subject to universal explosives screening.
X-ray baggage screenings weren't introduced until the 1950s.
Signs warned passengers from bringing weapons and explosives, but screenings were lax by today's standards.
More stringent security checks at John F. Kennedy Airport in 1970 caught weapons such as guns, daggers, and hand grenades.
In 1973, the FAA mandated the use of magnetometers and X-ray machines to screen passengers and carry-ons on commercial flights.
Full-body scanners wouldn't arrive until 2007.
Many airports had kiosks with life insurance vending machines geared toward nervous flyers.
Before 9/11, people who weren't flying could obtain gate passes and access the gate area.
There were also no restrictions on bringing liquids or gels in carry-on bags back then.
The first security lines at San Francisco International Airport formed in 1973, with an express line for passengers with no carry-ons.
Separate lines for TSA PreCheck and CLEAR didn't exist yet.
There was no TSA at all — private contractors screened passengers until the federal government took over airport security in 2002.
The computer monitors used for automated explosives detection systems were much clunkier than they are today.
The knives and box cutters that the hijackers used on 9/11 were legal to bring on planes at the time. After that day, flying was never the same.
