Horsetooth Mountain Park has a $6/day user fee or an annual pass for $65. We ride their often in the summer and also use the trails for hiking a fair amount as well. I don’t mind paying because we do utilize the trails on a regular basis.
It is not just one trail – it is a network of trails and a few different trailheads. There was recently two new trailheads/parking areas opened up and a new trail that connects three open space areas. Made for more quality singletrack in an already diverse area.