We are currently at the Boulder County Fairgrounds campground in Longmont, CO
They have a dump station, but no sewer hookups at the spots
spots have water and electricity though
You can get a spot for $15 without anything, $20 with water, $20 with electric, both electric and water $25
Maximum stay is 14 days, which is enforced
It is central, walking distance to a lot of places, including the fairgrounds itself, that has lots of interesting events including a farmers market on Saturdays.
There are a lot of dog walkers here, as there is a humaine society on the corner and the volunteers walk dogs all the time.
You cannot make reservations, but it has not been super busy even on the weekends.