Transport Minister Opens Thailand's Longest Railway Tunnel in Lampang
Deputy Prime Minister and Transport Minister Phithat Ratchakitprakarn presided over the breakthrough of Ngao Tunnel, now Thailand's longest railway tunnel at 6.2 kilometers, in Lampang Province. The tunnel is part of the Den Chai–Chiang Rai–Chiang Khong dual-track railway project, with excavation expected to finish this December and the full line targeted to open by 2028.
Lampang — Deputy Prime Minister and Transport Minister Phithat Ratchakitprakarn chaired the breakthrough ceremony for Ngao Tunnel in the Den Chai–Chiang Rai–Chiang Khong railway project, Contract 1, Den Chai–Ngao section, in Ngao District, Lampang Province. Attendees included Permanent Secretary of Transport Piyapong Jiwattanakulpaisal, State Railway of Thailand Governor Anant Phonnimdaeng, Lampang Deputy Governor Patchara Simasathien, Phrae Deputy Governor Chaisit Chaisamritphon, and Ngao District Chief Somjit Chulcharoen.
Phithat stated the breakthrough marks a major milestone in developing Thailand's rail infrastructure, particularly building tunnels through complex mountainous geology using modern construction technology and careful planning. It demonstrates Thailand's engineering capability and ability to manage large-scale projects to enhance rail network efficiency, safety, and future passenger and freight capacity.
Anant said the State Railway of Thailand closely oversees the project, especially tunnel sections with challenging terrain and varying geological conditions requiring specialized techniques and strict safety standards at every stage. The railway agency will accelerate remaining construction while maintaining quality and safety to complete the project on schedule for a 2028 opening.
Ngao Tunnel, located in Ngao District, spans 6,215 meters, making it Thailand's longest railway tunnel. Like the Song Tunnel in Phrae, it cuts through complex geological formations including the Pha Daeng, Wang Chin, and Khaeng Pla rock groups, comprising thick limestone and volcanic rock hundreds of millions of years old.
Excavation began on December 22, 2023, with 24.30 meters remaining and completion expected this December. After excavation finishes, the railway will proceed with structural work and installation of engineering systems, including track and safety systems, before system testing and commissioning ahead of the planned 2028 service launch.
