I'd definitely look for back roads and bike paths - sidewalks are about as treacherous (but of course you collide with things other than moving tonnage)... pretty hard to *ride.* Or just swipe some cones from a construction zone and put them on both sideds of the block you want to go up & down :-)
I've heard too many stories of folks taking out their bikes when they're on roof racks... those garage roofs, drive-thru's, etc. Hitches I can reach