earth foundation gravel ground limestone Mineral minerals nature path peat peat rock piedra piedras road rock rocks stone stones texture textures arcs curves Fractal fractals infinite jam jammed lost maze roads shapes street streets sundfractals traffic cobblestone dust moss old pavement paver pebble pebbles sand walk architecture city cross decay grunge grungy industrial no parking parking urban urban decay yellow yellow cross cobble connections network beach color colorfull colors colour colourfull colours round sea wet stones brick bricks cityscape concrete crack driveway floor floring mason masonry ornamental pavers streetscene