A Security Guard controls the barrier gate of the Richards Majestic Facility from inside his Security Booth in Grand Theft Auto 5

Barrier Gates control the entrance and exit into and out of highly sensitive facilities such as Military Bases and Movie Studios

These barriers are usually controlled electronically by a Security Guard from inside a Security Booth

Trespassing and/or breaking through the Barrier Gate will often result in an award of a number of Wanted Levels, depending on the type of facility you've broken into