What does the 'BTS' stand for in Bangkok's elevated BTS Skytrain system?

BTS stands for Bangkok Mass Transit System, the elevated rapid-transit network commonly called the BTS Skytrain in Bangkok, Thailand.

The system opened on 5 December 1999 after Bangkok’s severe traffic congestion created demand for a reliable urban railway. It was developed under a concession involving the Bangkok Metropolitan Administration and is operated by Bangkok Mass Transit System Public Company Limited. The name “Skytrain” describes its mostly elevated construction, not a separate railway system.

A common mix-up is confusing BTS with Bangkok’s MRT. The MRT is a different rapid-transit network, operated on separate lines that include underground sections, while the BTS primarily uses the Sukhumvit and Silom corridors. Bangkok also has other rail services, including the Airport Rail Link and State Railway of Thailand lines, so “BTS” specifically identifies this elevated system rather than Bangkok transit as a whole.

The BTS network’s central interchange is Siam station, where the Sukhumvit and Silom lines connect. Its formal Thai name is considerably longer, commemorating the sixth cycle birthday of Thailand’s king.