Do you have to call ahead to use the pavilion or can you just get there early and claim it.im wanting to use it for a birthday party and I have never done this before so I didnt know how it worked.

It falls under St. Peters Parks and Rec Dept. The number can be found on the city website, and they'll let you know if it's available and how much it costs. Depending on the time of year, you may need to book well in advance.

You do need to reserve but have to be a St. Peters resident. They will post a reservation notice on the front left side of the pavilion if it is reserved.

Call city of st. Peter's Parks Department

I would try St. Peters city hall, they can give you answer and maybe a reservation!