Yes...when driving in, there are numerous spots for larger trucks/trailers to park, before you reach the bathrooms. If you pass them up, there is an easy turn-around at the end. There are no signs saying you cannot sleep overnight, and usually there are quite a few overnighters already there.
You can stay up to 8 hours in any 24 hour period
You are allowed to stay for up to 8 hours in a 24 hour period. There are signs that state that overnight camping is not permitted. That being said, you usually see some overnighters there. As you drive in, you will see spots designated for larger vehicles/trailers. That would be the best spot for your 20 ft trailer. Stay overnight at your own risk (given the prohibitive signage).
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