10. Eisenhower Tunnel (CO) – 1.7 miles; high-altitude road tunnel in Rockies.
Longest Tunnel in the United State
9. Anton Anderson Tunnel (AK) – 2.5 miles; shared road-rail tunnel to Whittier.
Longest Tunnel in the United State
8. Cascade Tunnel (WA) – 7.8 miles; longest U.S. rail tunnel through Cascades.
Longest Tunnel in the United State
7. Ward Tunnel (NY) – 9.5 miles; supports NYC’s water system.
Longest Tunnel in the United State
6. Deer Island Tunnel (MA) – 9.5 miles; releases treated wastewater offshore.
Longest Tunnel in the United State
5. Sudbury Aqueduct (MA) – 16 miles; historic Boston-area water conduit.
Longest Tunnel in the United State
4. MetroWest Tunnel (MA) – 17.6 miles; modern water tunnel for Boston area.
Longest Tunnel in the United State
3. Hultman Aqueduct (MA) – 17.8 miles; key Boston water delivery tunnel.
Longest Tunnel in the United State
2. Quabbin Aqueduct (MA) – 25 miles; connects major reservoirs for Boston.
Longest Tunnel in the United State
1. Delaware Aqueduct (NY) – 85 miles; world’s longest tunnel; supplies NYC water.
Longest Tunnel in the United State