Third Longest Bridge (18 miles) Atchafalaya Basin Bridge, I-10, Louisiana, USA

The Atchafalaya Basin Bridge, also known as the Louisiana Airborne Memorial Bridge, is a pair of parallel bridges in the U.S. state of Louisiana between Baton Rouge and Lafayette which carries Interstate 10 over the Atchafalaya Basin. With a total length of 96,095 feet (29,290 m; 18 mi; 29 km), it is the third longest bridge in the US, the second longest on the interstate system, and 14th-longest in the world by total length.

The bridge was opened to the public in 1973, construction was said to have begun in 1971. At the time of its completion, it was the second longest bridge in the United States, behind the Lake Pontchartrain Causeway Bridge. The bridge includes two exits: one for Whiskey Bay (Louisiana Highway 975) and another for Butte La Rose (LA 3177). While the bridges run parallel for most of their length, they merge when crossing the Whiskey Bay Pilot Channel and the Atchafalaya River. The average daily traffic count is (as of 2015) 30,420 vehicles.

Accidents occur frequently near the two river crossings as both are very narrow and lack shoulders.Accidents along the bridge can be problematic as the Atchafalaya Basin is sparsely inhabited. In 1999, Governor Mike Foster lowered the speed limit on the bridge from 70 to 60 mph (115 to 95 km/h). In 2003, the Louisiana Legislature enacted new traffic regulations for the bridge. The speed limit for 18-wheelers was lowered to 55 mph (90 km/h), and they must remain in the right lane while crossing the bridge.