A vehicle has a seat on which a passenger sits, wherein the seat is bench-shaped and has a sitting portion, a backrest portion, and a supporting portion which supports the sitting portion and the backrest portion, wherein at least one of the sitting portion and the backrest portion is detachable from the supporting portion, wherein when the sitting portion is detachable, the sitting portion has a plurality of sitting regions which are arranged side by side in the right-left direction and have different thicknesses in the up-down direction, and wherein when the backrest portion is detachable, the backrest portion has a plurality of backrest regions which are arranged side by side in the right-left direction and have different thicknesses in the front-rear direction.