Typically you will find open tables for a BBQ at 5PM on Sundays. Remember that non reservable areas are first come first serve, so there are no guarantees. If you were planning on having a BBQ on a holiday you may not find a table / BBQ pit. For more questions call the ranger office at 408-259-5477.
Open picnic areas are first come first serve. I've typically seen advance parties come and setup as early as 11am. There are also areas, gazebos etc that you can reserve, thesr are mostly in shaded areas with kids play ground nearby.
Yes, you will need reservations before your event.
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