A vehicle (30, 130, 230, 430) drivable in use by a person walking or running whilst supported on a seat comprising: a frame; a seat for supporting a user's weight whilst walking or running; a non-steerable, free-wheeling large diameter front wheel which is free-wheeling and non-steerable with respect to the frame and the seat; the frame being configured to carry the seat suspended on the front wheel axle above the front wheel so as to carry most of a user's weight on the front wheel; and wherein, when a user is supported on the seat, a user's legs are arranged either side of the front wheel and a user's feet can engage with the ground for walking and running; a small diameter, steerable rear wheel journaled to the frame at a rear wheel steering pivot axis; the seat being rotatable forwardly with respect to the front wheel; the seat comprising a seat base for supporting a user; characterised in that: the seat is freely rotatable from its position above the front wheel forwardly with respect to the front wheel to allow a user to dismount forwardly, and the seat comprises a backrest for engaging a user's back in use, and the back rest prevents the seat rotating forwardly in use by a person walking or running whilst supported on the seat; and, in which the vehicle (30, 130, 230, 430) is free of obstructions to the front of a user on the seat enabling a user to dismount forwardly, either by choice or in the event of the vehicle (30, 130, 230, 430) stopping suddenly for some reason; and, in which the vehicle (30, 130, 230, 430) comprises at least one steering mechanism to aid steering the vehicle into a turn comprising the tiltable rear wheel steering pivot axis for the rear wheel, tiltable rearwardly and forwardly with respect to the frame between a first initial position and a second position in which it is inclined rearwardly so that the top of the rear wheel steering pivot axis lies rearward of the bottom of the rear wheel steering pivot axis when the vehicle (30, 130, 230, 430) is viewed from the side. a frame; a seat for supporting a user's weight whilst walking or running; a non-steerable, free-wheeling large diameter front wheel which is free-wheeling and non-steerable with respect to the frame and the seat; the frame being configured to carry the seat suspended on the front wheel axle above the front wheel so as to carry most of a user's weight on the front wheel; and wherein, when a user is supported on the seat, a user's legs are arranged either side of the front wheel and a user's feet can engage with the ground for walking and running; a small diameter, steerable rear wheel journaled to the frame at a rear wheel steering pivot axis; the seat being rotatable forwardly with respect to the front wheel; the seat comprising a seat base for supporting a user; characterised in that: the seat is freely rotatable from its position above the front wheel forwardly with respect to the front wheel to allow a user to dismount forwardly, and the seat comprises a backrest for engaging a user's back in use, and the back rest prevents the seat rotating forwardly in use by a person walking or running whilst supported on the seat; and, in which the vehicle (30, 130, 230, 430) is free of obstructions to the front of a user on the seat enabling a user to dismount forwardly, either by choice or in the event of the vehicle (30, 130, 230, 430) stopping suddenly for some reason; and, in which the vehicle (30, 130, 230, 430) comprises at least one steering mechanism to aid steering the vehicle into a turn comprising the tiltable rear wheel steering pivot axis for the rear wheel, tiltable rearwardly and forwardly with respect to the frame between a first initial position and a second position in which it is inclined rearwardly so that the top of the rear wheel steering pivot axis lies rearward of the bottom of the rear wheel steering pivot axis when the vehicle (30, 130, 230, 430) is viewed from the side. the seat is freely rotatable from its position above the front wheel forwardly with respect to the front wheel to allow a user to dismount forwardly, and the seat comprises a backrest for engaging a user's back in use, and the back rest prevents the seat rotating forwardly in use by a person walking or running whilst supported on the seat; and, in which the vehicle (30, 130, 230, 430) is free of obstructions to the front of a user on the seat enabling a user to dismount forwardly, either by choice or in the event of the vehicle (30, 130, 230, 430) stopping suddenly for some reason; and, in which the vehicle (30, 130, 230, 430) comprises at least one steering mechanism to aid steering the vehicle into a turn comprising the tiltable rear wheel steering pivot axis for the rear wheel, tiltable rearwardly and forwardly with respect to the frame between a first initial position and a second position in which it is inclined rearwardly so that the top of the rear wheel steering pivot axis lies rearward of the bottom of the rear wheel steering pivot axis when the vehicle (30, 130, 230, 430) is viewed from the side.