20 Baht - Rama IX Thai Railway

Issued to mark the centenary of Thai state railways, founded in 1897 under Rama V, who had pushed aggressively for rail infrastructure as a tool of territorial consolidation — particularly to bind the northern and northeastern regions to Bangkok at a moment when French and British colonial pressure on Siam's borders was acute. The network's first line ran from Bangkok to Ayutthaya.

By 1997, the commemorative program under Rama IX had become one of the most prolific in Southeast Asian numismatics, making individual issues from the period relatively common in uncirculated condition.