Colorado's Eisenhower Johnson Memorial Tunnel, an engineering feat, is also significant for its connection to Janet Bonnema, engineer and women’s rights advocate. In 1970 Bonnema applied for a Colorado Department of Highways (CDH) engineering position that required work at the tunnel construction site. CDH hired her, believing she was male. When CDH realized the error, they denied Bonnema access to the tunnel due to a myth that it was bad luck for women to enter tunnels. Bonnema filed a sexual discrimination lawsuit against CDH. She settled out of court, having earned the right to work in the tunnel. To much fanfare, Bonnema entered the tunnel for the first time on November 9, 1972. Over sixty male workers temporarily walked off the job in protest. She persevered and continued to work in the tunnel, collecting samples and taking measurements, until the first bore's completion in 1973. Her determination opened the door for Colorado women to pursue careers in the transportation sector.