https://kids.guinnessworldrecords.com en

Longest water supply tunnel

Longest water supply tunnel
Who
West Delaware tunnel
Where
United States
When
1944
The longest tunnel of any kind is the New York City West Delaware water-supply tunnel, begun in 1937 and completed in 1944. It has a diameter of 4.1m 13ft 6in and runs for 169km 105miles from the Rondout reservoir into the Hillview reservoir, in Yonkers, New York, USA.