Garages and Outbuildings

Need to build a ramp in the backyard up to the level of the alley out back. Alley is about 10" higher than the patio - we want to park a car back there. the ramp would be about 8' wide, and should probably be 2' deep or more, our car is fairly low to the ground. Can be wood tie and steel plate construction, or concrete, or another solution you propose. Need this done by July 27