05/23/2026
The Dearborn Assembly Plant (DAP) was the spiritual and historical home of the Ford Mustang. Operating within the massive River Rouge Complex, the plant produced roughly 6.7 million Mustangs from its very first day of production in March 1964 until it officially closed in May 2004.
A deep dive into the history of the Dearborn Assembly Plant uncovers several fascinating chapters:
WWI Origins as a Submarine Factory: Designed by famed architect Albert Kahn, the building wasn't originally intended for cars. It was erected in 1918 to construct "Eagle Boats" (submarine chasers) for the U.S. Navy before transitioning to Model Ts, Model As, and tractors.
The Birth of the Pony Car: The very first production Ford Mustang officially rolled off the DAP line on March 9, 1964. Workers initially struggled to keep up with the staggering demand, building the cars at an incredible pace of 70 units an hour.
The "B" Building Legacy: As part of the wider River Rouge Complex, DAP was known internally as the "B" Building. Because of its integration within the Rouge, the plant had access to its own blast furnaces, steel mills, and glass plants, making it a completely self-sufficient manufacturing powerhouse.
40 Years of Continuous Production: DAP is the only facility that built the Mustang continuously for its first 40 years, surviving numerous platform redesigns—including the classic early years, the famed Fox-body era, and the SN-95 updates.
The Final Curtain: The last Mustang to roll off the historic DAP assembly line was a red 40th Anniversary GT convertible, completed on May 10, 2004. Afterward, the facility was largely demolished, and modern Mustang production moved to the Flat Rock Assembly Plant.
To dive deeper into the history of this iconic factory or take a walk down memory lane, check out the OnAllCylinders feature on DAP’s 40 years of Mustang production or read MotorTrend's retrospective on walking the historic assembly line.
