It was actually a double playground day. After the beach attempt (too crowded), we went to the playground near our house (it is a great playground). We stayed for over an hour and went back to the house for lunch and nap. After nap, he woke up, called for me, and asked for the playground again.
He's not really into the whole "water" thing. Pools, beaches, he doesn't care too much for them. Put the kid in a sandbox or on a swing though -- nothing but glee!