A seat for a land vehicle, aircraft, or watercraft, comprising a textile seat portion having a seating surface and a backrest with a supporting structure for the seat portion configured as a support frame extending about the seat portion. The support frame is in the form of a textile strap guided through vehicle-mounted eye rings. Portions of the strap extend laterally of the seat portion in the form of diagonal strap portions that each extend between one of the eye rings mounted below the seating surface and one of the eye rings mounted above the backrest. The seat portion is displaceably disposed on the diagonal strap portions. At least one adjustment strap is guided from the backrest to a fixation mechanism disposed above the seat portion.