Soi 1 Guesthouse Bangkok - a comfortable affordable backpacker and traveller's rest in Sukhumvit, central Bangkok
Skytrain
The Bangkok Skytrain (BTS, pronunced bee-tee-et in Thai) deserves a visit simply for the Disneyland space-ageness of it.
Built in a desperate effort to ease Bangkok's insane traffic and pollution, the Skytrain covers most of downtown and is especially convenient for visiting the Siam Square area. There are two lines: the light green Sukhumvit line which travels along Sukhumvit road, and the dark green Silom line, which travels from the Silom area, interchanges with the Sukhumvit line at Siam Square (C) and terminates near the Chatuchak Weekend Market (N8).
At time of writing, the line extensions aren't running yet, but soon there will be direct BTS access from the Airport !
Soi 1 Guesthouse is 300 meters from the (E2) Phloen Chit stop.
There isn't, unfortunately, a station near Banglampu District (aka the Khao San Road area) but we can get you there from Soi 1 Guesthouse on the Canal for less that 30 baht.
You must have 5 or 10 baht coins to purchase Skytrain tickets from the vending machines near the entrance, so hold on to them. Fares range from 10 to 45 baht depending upon how many zones you are travelling. Consult the map (in English) near each ticket machine. If you do not have coins, you may need to queue for change from the staff at the booth. If you are in town for several days, weigh your options and consider a rechargable stored-value card (200 baht), a "ride all you like" tourist pass or a multiple ride pass of 10 trips or more. They will certainly save you time, scrambling for coins, and maybe even money. Check for information with the English speaking staff.
Metro
The Blue Line connects the central Hualamphong railway station (1) to the northern Bang Sue station (18), with interchanges to the Skytrain at Silom/Sala Daeng (3/S2), Sukhumvit/Asok (7/E4) and Chatuchak/Mo Chit (15/N8). You can also transfer to north/northeast-bound SRT trains at the northern terminus Bang Sue.
Metro tickets are not interchangeable with Skytrain tickets. Rides cost from 12 to 36 baht depending on distance; a 300 baht stored value card is also available. For single ride fares, a round plastic token is used.
The metro system does have a few quirks in terms of locations — the subway stop for the Chatuchak Weekend Market is not Chatuchak Park, but one stop further at Kamphaeng Phet (16). The latter drops you right inside the market.