Is it possible to visit Pattaya for the day from Cha am? if so what is the best way to travel?
Too far for a day trip, it is about 4.5 hours by van each way from Hua Hin, even if you arranged a car+driver to take you there for the day it is going to be about 4 hours each way, so you won't have much time to see anything.
Overnight is an option but depends if there was something specific you wanted to see there.
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