The rail network in Thailand is fairly limited but it does span the length of the country and reach all major centres. Trains are generally slow but reliable and comfortable, and still favoured as a budget and charming means for tourists to get around, especially on overnight sleepers.
All trains begin from Bangkok and span outwards. Long distance trains depart from the centrally located Hua Lampong station which is serviced by the city’s metro system. From here trains depart several times a day to Chiang Mai and stations on the northern line, and as far as Nong Khai on the northwest border with Laos. Trains also reach Pattaya and the Cambodian border in the east, Kanchanaburi in the west and all the way south as far as the Malaysian border. The closest it gets to Phuket, Krabi or Samui is Phun Phin station near Surat Thani, where there are minibus transfers.
The two most popular routes for tourists from Bangkok are to Chiang Mai (north) and Hat Yai (south), although budget flights have now made the train a redundant choice since you can save up to 10 hours of travel for an additional few dollars in ticket price for an airline seat. At least five trains depart per day in both directions, taking 12 hours to get to Chiang Mai or Phun Phin (average price is around 800 baht for second class), with several sleeper trains leaving in the evening for an overnight journey (note: not all evening departures are sleepers).
First class gives you your own compartment, or shared, but it’s almost as expensive as an airline ticket. Far more popular is second class which is quite clean and comfortable with about two dozen lower and upper bunks stretched the length of the carriage. Lower bunks are preferable, but you can get a decent night’s sleep in either, depending on snoring passengers. Lights remain on in the cabin all night, but your have a bunk curtain for privacy. Basic food, snacks and soft drinks are served.
Third class is a bit rough and tourists seldom use it. Pre-booking is suggested in the high season such as December, mid-April or late November, or weekends. It’s possible to catch a single daily train as far as Butterworth near Penang in Malaysia.