King Rama VI had developed the domestic communications in many fields:
Improved and expanded business of the State Railways since 2460/1917.
The drilling of Khuntan Mountain to make the longest rail track tunnel was successfully completed during his reign resulting in train services from Bangkok to Chiang Mai to be operable
Opened the Southern line for operations from Thonburi Station for connection with Malayan (Malaysian) trains and on to Penang and Singapore
Connected all railways in the Royal Kingdom for linking with Hualamphong Central Station
in 2462/1919, established Army Aircraft Department whereby air postal parcel services between Bangkok and Chanthaburi were in operations for the first time and commanded Highway Department to construct the roads in all regions.