I have found really impressive road map of tree city and tree city area prepared by some anonymous cycling enthusiast. The map is enriched with photographs and short notes concerning road surface types and traffic (unfortunately in Polish). Very useful for cyclists visiting 3City---other maps do not contain information on traffic/surface.
Roads marked with green and blue denotes paved roads, marked with red denotes paved road as well but with high traffic. Yellow denotes unpaved surface. Orange and pink denotes paved road but not particularly suitable for cycling (cobblestones, concrete road slabs etc)
