Clifford Milburn Holland

Holland, the engineer who designed it, but he died suddenly before the tunnel’s completion. The north tube is 8,558 feet (2,608 metres) long and the south tube 8,371 feet (2,551 metres) long. The roadway is 20 feet (6.1 metres) wide and reaches a maximum depth…

…engines, was successfully solved by Clifford Holland for the world’s first vehicular tunnel, the Holland Tunnel, completed in 1927 under the Hudson River. Holland and his chief engineer, Ole Singstad, solved the ventilation problem with huge-capacity fans in ventilating buildings at each end, forcing air through a supply duct below…