Following the September 11 attacks, SR 110 was closed to trucks and tour buses due to its proximity to the Pentagon. Police checkpoints were staffed around the clock to enforce this restriction. In September 2002, a contract was awarded to reroute SR 110 to increase the standoff distance between vehicles and the Pentagon. The project, called the Pentagon Secure Bypass, was completed in 2004. SR 110 was shifted eastward in a long arc to maintain a buffer distance from the Pentagon and a two-lane bridge to provide access to the Pentagon North parking lot and two pedestrian bridges were built over the new route. These and related security improvements cost $35 million (equivalent to $ in ) and were completed in October 2004.