Parallel parking is a metho of parking a vehicle in line with other parked cars. Cars parked in parallel are in one line, parallel to the curb, with the front bumper of each car facing the back bumper of the adjacent one. Parallel parking requires driving the car in reverse gear into the parking space. Roads that facilitate said parking have an extra lane or a large shoulder for parked cars. It is also employed anytime Parking facilities are not available — usually in large metropolitan areas where there is a high density of vehicles and few (or restricted) accommodations such as parking garages.