Thailand’s Ministry of Transport has commenced tunnelling works under the Chao Phraya River as part of the MRT Purple Line southern extension in Bangkok. This marks the second cross-river tunnel for Bangkok’s metro system and a major milestone in expanding the capital’s rail infrastructure.
According to Transport Minister Suriya Jungrungreangkit, the extension is 60 percent complete and ahead of schedule. The 23.6 km route will run from Tao Poon to Rat Burana, featuring 10 underground and seven elevated stations. The first phase—Tao Poon to the National Library—is targeted for completion in 2028, with full operations expected by 2030.
The extension will enhance connectivity through integration with the existing MRT Blue and Purple lines at Tao Poon. The ministry has emphasised strict adherence to safety, environmental, and traffic management protocols throughout construction. In parallel, Thailand will launch a THB20 flat fare for Thai citizens using any of Bangkok’s eight electric train lines, beginning October 2025.