In the mid-1950s, the Ventura Freeway, which bisects the town, was completed from Los Angeles to points north, making it an easy one-hour trip to Camarillo. The freeway was originally planned to follow the path of Potrero Road, south of Camarillo, which would have completely by-passed the soon-to-be city. However, after much debate, city officials persuaded Caltrans to lay the freeway parallel to Ventura Boulevard, creating the infamously steep descent from the Santa Monica Mountains, known as the Conejo Grade. The grade is about and posted as a 7% grade—which translates as about one thousand feet of elevation change in less than three miles (70 meters per kilometer). There is a California Highway Patrol brake inspection station at the top of the grade and a stop is mandatory for all 18-wheel trucks. The completion of the freeway facilitated the growth that followed. In 1962, the population was 7,500 and 3M began construction for the Mincom and Magnetic Tape Divisions, which would ultimately employ 900 people, becoming the largest local employer. That plant briefly housed a factory for 3M spinoff Imation before being closed in 2008.