The raging waters in the river from the snowmelts was moving very quickly. We did not dare put out toes in that cold, swift waters for fear of being dragged down stream - not to mention the hypothermia. It was really, really cold.
The visitors center offers a film about the park. There is an Ansel Adams gallery and outfitters store for those inclined to hike. There are several restaurants.
And please take the shuttle buses, as they are much easier on you and the patrons of the park.
It was crowded, as we were there on a weekend, but the shuttle buses make it a snap to get around. You can even ride your bikes to almost everything if you wish - but be wary of the traffic as there were lots of cars on every roadway.