https://ny.curbed.com/maps/nyc-subway-secret-tunnels
The North River Tunnels connect Manhattan to New Jersey and the West. 820,000 people and 450 trains pass under the Hudson River through these 2.5 miles tunnels every day. But these tunnels were built 120 years ago and they are showing their age. Now, New York has a dangerous tunnel problem on its hands. https://www.youtube.com/watch?v=48_FHhRQdt0 zz
