The northern line has four tunnels. The longest is Khun Tan Tunnel in Lamphun Province at 1,362 metres long. It is presently the longest in Thailand.
- Pang Tup Khop (KM 513.721-513.841): 120 metres
- Khao Phlueng (KM 516.411-516.773): 362 metres
- Huai Mae Lan (KM 574.048-574.178): 130 metres
- Khun Tan (KM 681.579-682.941): 1,362 metres
RELATED LINKS: Bridges on the Northern Line