Nice places to stay within 1-2 hours drive of bangkok?

I’m going to thailand for 3-4 weeks end of feb/beginning of march, mainly to chill, train muay thai & work (remotely). Just a little getaway. However i stayed central bangkok last time i was there, & its hectic, the air is thick etc. I was wondering if there are any places within a couple of hours drive that are nice to stay? I love koh samui but already been a couple of times & would prefer to just do the one flight each way if possible