A crosswalk for the Ages

 Our feet have spent many miles in the past 3 days walking on cobblestone roads.  Each cobblestone is a rock shaped like a cube 4" on a side. 

 They are typically arranged "subway tile" fashion at a 45° angle to the direction of travel.

Cobblestone roads are much better to walk on than asphalt, 'cause you can hear the cars coming, and they don't usually drive as fast.

Crosswalks are made by using contrasting color stones.  If laid properly, I'd wager the crosswalks will be visible for centuries: it takes a long time to wear through 4" of rock.