Soapstone Prairie Open Space, south trailhead parking area.

 Brochure, (printable and recommended to bring): Soapstone Prairie trails map-brochure

 Gravel bike ride on double-track gravel:
  ~20-miler with less-than-~1600-vertical-feet.

 Route: Cheyenne Rim Trail, double-track; Canyon Trail; Sand Wash Trail; Rawhide Flats Road; ....

 Map: https://ridewithgps.com/routes/34560264.

 Mountain bike or gravel bike ride on double- and (mostly) single-track gravel: Similar, alternative route, slightly more difficult, >21-miler with ~1700 to ~1850-vertical-feet: Cheyenne Rim Trail, single-track, mostly; Canyon Trail; east side of Mahogany Loop; west side of Pronghorn Loop; ...

[Soapstone Prairie bike route(JPG screenshot).]  

 Map of alternate-route: https://ridewithgps.com/routes/34565922

 A bring-your-own lunch/BBQ afterwards in the South Trailhead lot.