We wandered into this area from Haggin Park, but it is actually a little closer to River Bend Park. If you come from River Bend, just know that you have to pay for parking. The geo-kids and I have wandered through this area several times with our cub scout pack. We have our day camp right around the corner from here.
The coordinates were giving me a bit of trouble. Averaged a bunch of different readings. None of them were more than 5 feet off from the average, but let me know if you get something different.