Construction of the first two lines began May 23, 1962 under the supervision of the Director of Public Works, Lucien L'Allier, the "father of the subway". On June 11, 1963 the construction costs for tunnels being lower than expected, Line 2 (Orange Line) was extended by two stations at each end and the new termini became the and stations. The project, which employed more than 5,000 workers at its height, and cost the lives of 12 of them, ended on October 14, 1966. The service was opened gradually between October 1966 and April 1967 as the stations were completed.