Clark
Clark Veterans Cemetery
Clark Veterans Cemetery is inside the Freeport and holds graves of American veterans and Filipino Scouts. The old Fontana site listed it as a nearby place, which is geographically true and tonally different from a pool day.
Visit in the morning, dress as you would for any cemetery, and do not fold it into a casino evening. It is a short, sober stop, not an attraction with rides.
Pair it with Fort Stotsenburg notes if you want one history hour, then return to the park for the rest of the day.