Making a 2d Track Sprite.

I have a 2d car controller and I am looking to make a nice car track in probably photoshop. Is my best way to go about this to just make a giant JPEG and importing it into the game scene? I feel a gigantic image may not be the best way to do this but then again I can't see another way. What would the dimensions need to be? 10000px^2? Would this not be bad for load times and game size if I have a bunch of maps like this?

Thanks