Holland Tunnel

     The Clifford Milburn Holland Tunnel (more commonly known as the Holland Tunnel) is a highway tunnel under the Hudson River connecting the island of Manhattan in New York City with Jersey City, New Jersey at Interstate 78 on the mainland of the United States.

     Begun in 1920 and completed in 1927, the tunnel is named after Clifford Milburn Holland (1883–1924), Chief Engineer on the project, who died before it was completed. Tunnel designer Ole Singstad finished Holland's work. The tunnel is one of the earliest examples of a mechanically ventilated design.

    The tunnel consists of a pair of tubes, each providing two lanes in a 20-foot (6 m) roadway width and 12.5 feet (3.8 m) of headroom. The north tube is 8,558 feet (2,608 m) from end to end, while the south tube is slightly shorter at 8,371 feet (2,551 m). Both tubes are situated in the bedrock beneath the river, with the lowest point of the roadway approximately 93 feet (28 m) below mean high water.