Horizon Golf & Beach - Confused

I thought I was going to Oyama Regional Park, but ended up at a place called Horizon Golf & Beach. The front office/concession was closed all day and I couldn't really tell if anybody worked there but it looked like a lot of people were out there camping but I haven't been able to find a number to book a spot. I fished for a couple hours but all I caught was a boot(literally) and left.