The challenge of getting to Hua Hin is one of the reasons it is not as developed as many of Thailand's other beach resorts. Many would say that's a good thing. There have been a few attempts over the years to offer flights to Hua Hin from Bangkok, but these have never proved successful. A few five-star hotels can still arrange it, but otherwise you'll either have to go by road or rail.
The trip by road takes about two to two-and-a-half hours, depending on traffic. Most hotels in Hua Hin can arrange for a private transfer, or you can take a bus from Bangkok's Southern Bus Terminal.
The train is the "classic" way to get to Hua Hin. The train station, with its delicately designed royal waiting room, is just a short walk from the center of town. The journey takes about four hours. All Southern Line trains stop in Hua Hin. See the State Railway for a current time schedule.