Take a trip along US 40 in eastern Ohio and you will see several "S" bridges, remnants of the original National Road along the current US 40 roadway. Over the years I have heard some urban legends about why these bridges are "S" shaped. Here they are:  The bridge designers and bridge builders got drunk in a bar one night. The bridge designers bet the bridge builders they couldn't build an "S" bridge; the bridge builders bet the bridge designers they could design an "S" bridge. and .......The "S" shape was designed to slow drivers down as they hit the potentially wet brick bridge surface as it crossed a stream below.  The real reason for the unique shape of the "S" bridge is simple: often the road and the stream did not cross at neat 90° angles. Today's road building techniques would keep the road straight and build the bridge at an angle; but when using brick and stone it was simpler and cheaper to bend the road and keep the bridge straight with what it was crossing.  **Photo © Leslie Dellovade, ODOT

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