This is the fifth and final Route 66 alignment bridge over the Mississippi River - from 1968 to 1977.

The bridge is 2,164-feet long and carries eight lanes of traffic for two Interstates and a U.S. Highway.

The east end of the bridge corsses the south end of what was "Bloody Island," which was connected to the mainland of Illinois with landfill in the 1850s by Robert E. Lee. Back when this was an island, several Missouri politicians fought duels here. The area is now a train yard.

While this bridge has had several official names over the years, its current official name is the "Congressman William L. Clay Sr. Bridge," which was designated in 2013. However, it's always been referred to "Poplar Street Bridge," even before it opened - because the Missouri end of the bridge sits over Poplar Street.