We had to get an overnight bus from Chaing Mai to Bangkok & then another bus in the morning to Kanchanaburi. We wanted to go by train but were convinced out of it by a dodgy travel agent, obviously they don't get commission from train tickets! The overnight bus was packed to the brim & we have bought so much stuff we had it all by our feet & it was a pretty uncomfortable ride! We got into Bangkok at about 6am & had to wait until 10.30 for our next bus to Kanchanaburi, that was a mini bus & we stupidly sat in the back row & had everybodies luggage piled over us! Luckily the bus ride was only about 2 hours.