It seems so at least n summer.
Yes, currently
the parking is free. however there may be an entrance fee for non fairfax residents time to time. Luckily I have been there twice this week and the gate was open for all with no entrance fee. So enjoy it as the park has a lot to offer. speaking of which, if you're looking forward to rent a boat try to be at dock as your earliest as there are a waiting list for people who want to use them.
I went this week and there is a label posted in the check in kiosk stating that currently there's no fees... I was going to the campgrounds, so I just paid for that. Don't really know why this sign is there... but it certainly happened.
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