The double-track railway along the State Railway of Thailand's southern line, which stretches from Nakhon Pathom and Chumphon, is officially open, the agency announced on Monday.
According to the head of SRT governor's office, Ekarat Sri-arayanpong, the newly opened track will improve logistical operations along the 421-kilometre route.
It will also cut journey times on the southern line by up to 90 minutes, which will make rail travel more appealing to tourists. As trains going in opposite directions now won't have to wait to pass each other, the upgrade will also improve the overall safety of the system.
The line starts in Nakhon Pathom and heads through Ratchaburi, Phetchaburi and Prachuap Khiri Khan before ending in Chumphon. It is mostly at ground level, except in urban areas, where they are elevated to prevent traffic congestion.
The line passes two major landmarks, the first being the bridge across the Mae Klong River in Ratchaburi, which the government intends to promote as the province's newest tourist attraction, and the new Hua Hin railway station, which retains the architectural style of the old station.
The SRT plans more dual-track stretches, including between Khon Kaen-Nong Khai and Nakhon Ratchasima-Ubon Ratchathani in the Northeast; Pak Nam Pho-Den Chai and Den Chai-Chiang Mai in the North; and Hat Yai-Padang Besar, Surat Thani-Songkhla and Chumphon-Surat Thani in the South.
By the time the upgrades are completed in 2029, Thailand will have 2,370 kilometres of dual-track railways, which will greatly improve the nation's logistic efficiency and appeal to tourists, Mr Ekarat said.
Mr Ekarat also said the Pha Sadet tunnel will reopen next month. The country's longest rail tunnel was shut the day after it opened on July 28 due to complaints about dust.
He said the decision was taken after a test on Aug 8 revealed excessive exhaust gases remained after a train went through.