My favourite "time off" places in California when I'm there are Iddylwild and Palm Springs. Iddylwild has no airport, and more's the pity.
Palm Springs has a nice little museum, but also quite a nice rental place called "Flight School in Palm Springs", where I have rented a couple of very nice aeroplanes. That was a couple of years ago, and my recollection was that they never seemed to check their emails so phone up. This seems to be their current details
The Flight School at Palm Springs
Palm Springs apart from being quite a pleasant town, has incredibly consistent good weather (so away, for example, from the fogs of the LA basin, or most mountain effects), and lots of good hotels - a few of which are cheap! (Try Alcazar:
Alcazar Palm Springs in Palm Springs, CA - Choose A Room).
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