What tunnel runs under the Hudson River and has a ventilation system innovated by Ole Knutsen Singstad?
Holland Tunnel The Holland Tunnel is a highway tunnel under the Hudson River between Manhattan in New York City and Jersey City, New Jersey. Its two tubes carry eastbound and westbound Interstate 78. In New Jersey, it is also designated NJ 139. An integral conduit within the New York Metropolitan Area, it opened in 1927 as the first of two vehicular tunnels under the river, the other being the Lincoln Tunnel. Both are operated by the Port Authority of New York and New Jersey.
Hudson River Waterfront Walkway The Hudson River Waterfront Walkway, also known as the Hudson River Walkway, is an ongoing and incomplete project located on Kill van Kull and the western shore of Upper New York Bay and the Hudson River, implemented as part of a New Jersey state-mandated master plan to connect the municipalities from the Bayonne Bridge to the George Washington Bridge with an urban linear park and provide contiguous unhindered access to the water's edge.