A ramp assembly includes a pair of ramps each that has a top surface, a bottom surface and a peripheral edge extending therebetween. Each of the ramps may be positioned to define an inclined plane between two surfaces. A powered wheel chair may be driven upwardly and downwardly along the ramps. A pair of lateral walls is coupled to the ramps. A roller is coupled to each of the ramps. The roller is positioned to be engaged by tires of the powered wheel chair when the powered wheel chair is driven on the ramps. The roller prevents the powered wheel chair from climbing the lateral wall and tipping from the ramps.