The land for the park was donated to the City of Riverside for use as a public park as long as those that wanted to could run live steam trains there. The city maintains the park and the club maintains the railroad property. The park also contains a baseball field, a field suitable for soccer or football and considerable area of rolling lawns. The sign was just being dedicated as I got there. Some of the club members were unhappy about the British prototype depicted on the sign.
All train rides are free, but donations are accepted.
Diesels are absolutely not allowed on the property. The closest that diesels get is the BNSF and UP main lines that run a half block west of the park. A fast train went by every 10 or 15 minutes. There is an engine service yard with many service track, two turntables and two transfer tables. There are also several substantial equipment storage buildings and a sort of a club house arrangement.