Big Break Visitor Center at the Delta

A natural history museum and staging point for paddling and hiking into the Sacramento-San Joaquin Delta, inside Big Break Regional Shoreline park in Oakley, with a boat and kayak launch, a fishing pier, and Delta wildlife exhibits. Run by the East Bay Regional Park District, it includes a walkable scale map of the entire Delta, giving visitors a genuinely useful orientation to the wider waterway system before heading out onto the water. It's a worthwhile stop if you're interested in the Delta specifically rather than just passing through on I-5, though it's a longer drive from Patterson than most of the other options on this list.