Roads can be all sorts of colours, often we can go a little on the dark side but the surface will soften over the years with weather, traffic etc. if you wish to represent the cant this can be a bit tricky and probably best ignored. A choice of slightly greyish emery paper can work quite well if the space needed is not too large. Another option make the road surface from Hardboard (EDIT indoors, outside Plastic Coated Foamboard end of EDIT), spray with cheep black sticky paint and immediately cover with Dry Silica Sand. Allow to dry drop off loose sand then a light spray of matt paints black, grey and a very very light dusting of white from a good distance will give a realistic look.