Tren

Tren
Train — Fast and efficient, the Mass Rapid Transit network (MRT) local train system serves 18 stations and stretches for 20 km in a horseshoe shape from Hua Lamphong in the South (near Chinatown) to Bang Sue in the north. Trains arrive every 5-7 minutes, and connect to the BTS Skytrain at Sukhumvit and Silom stations.
The Bangkok MRT underground runs underneath Rama IV and Ratchadapisek Roads, the two thoroughfares that cut through the heart of downtown Bangkok. Although additional lines and extensions are in the pipeline, it currently only comprises the blue line, serving 18 stations from Hua Lamphong to Bang Sue.
Fares are determined by the distance traveled. For adults, that means paying a one-way fare of 16 Baht if going to just one train stop, as opposed to 12 to 17 stops, which will cost 42 Baht for that one-way ride. For Children, such fares run from 8 Baht to 21 Baht. Unlimited passes are also available – running from one-day (120 Baht) to 30-days (1,400 baht).
Check the MRT website for more fare info, and a map of the train system:
https://www.mrta.co.th/en/service/service.php
In addition, there is another train service call the “Skytrain” (BTS). For now, BTS has just two lines:
SILOM LINE runs west to south, between the National Stadium in the Siam shopping area to Bang Wa in Thonburi (across the river).
SUKHUMVIT LINE runs north to east from Mo Chit to Bearing. The two lines meet at Siam Station, and also interconnect at two points with the underground (MRT) – at Sala Daeng and Asok stations. A new train arrives every 3 – 6 minutes or so between 06:30 and midnight. The last train leaves between 23:30 and 23:50. Fares start at 15 baht for one stop. See the following web pages for more fare info and a map of these train lines:
https://www.bts.co.th/customer/en/01-ticketing-type-sing-journey-ticket.aspx
https://www.bts.co.th/customer/en/02-route-current_new.aspx