Abstract: An omni-directional treadmill providing a surface with no gaps on which a user can move. The treadmill is generated by arranging a set of looped belts (1, 2, 10), each providing at least one elongated surface, abutting one another along the elongate edges provided by the elongate surface. A group of these elongate surfaces defines the treadmill surface. This set of belts (1, 2, 10) is itself arranged in a loop. Movement of the whole set of belts around this loop moves the treadmill surface in one direction. Simultaneous rotation of all the belts (1, 2, 10) providing the surface provides movement perpendicular to the first direction. Using these two components of motion the treadmill can move in any direction indefinetly. Feedback from user can be used to move the treadmill in the opposite direction to keep user in the same place, in the same way a treadmill maintains user moving in one direction in the same place.