Chiang Mai is 800 km north of Bangkok
(497 miles)
By plane
Chiang Mai International Airport (CNX) handles both domestic and regional international flights. The route from Bangkok is one of the busiest in the country (Thai Airways flies daily almost every hour, with additional flights in the peak tourist season).
The airport is some 3 km south-west of the city centre, only 10-15 minutes away by car. Legal airport taxis charge a flat 140 baht for up to 5 passengers anywhere in the city; if you take a metered taxi the price will be under 100 baht. The taxis operate from the exit at the north end of the terminal - after baggage claim and/or customs, walk into the reception hall and turn left. Alternatively, take bus #4 to the city center for 15 baht, or charter a tuk-tuk or songthaew for 50-60 baht. Most hotels and guesthouses offer cheap or free pick-up/drop-off services.
By bus
Buses to Chiang Mai leave from Bangkok's Northern Bus Terminal (Moh Chit). The cheapest, non-aircon, stop-everywhere government buses take around 12 hours; non-stop VIP 24-seaters manage the trip in 9 hours on a good day. Chiang Mai also has good bus connections to practically everywhere in the North, and major destinations/hubs in the North-East (Issan); there's even a direct service to Pattaya and Rayong in the East.
By train
Various rapid, express and sleeper services leave from Bangkok's Hualamphong station, taking 11+ hours for the trip. The day trains have only second and third class, with no sleeper berths. Sprinter trains are entirely second class air-con, also with no sleeping berths, and are the only ones which cannot transport bicycles.
The overnight trains - especially air-con and non-aircon second class sleepers - are very popular, safe, comfortable and fun; those who do not wish to share crowded "bathroom" facilities can book a private first class two-berth cabin (the attendant cleans the first class bathrooms frequently). In second class sleepers, the lower berth is more expensive than, but also wider than, the upper berth.