The construction work on the Walthamstow–Victoria section began in 1962. It continued until 1972, when Pimlico station was opened. A test tunnel from Tottenham to Manor House under Seven Sisters Road had been constructed in 1959 and this was later integrated into the running tunnels. The Prince of Wales and the Duke of Edinburgh visited the line during its construction. In July 1968, they visited the tunnels that were being built under Vauxhall Park.