There are actually two Thumb Rock Picnic Areas, Upper, and Lower. Both of them are located within a few steps of Peña Blanca Lake. Upper Thumb Rock is situated on a low hill, overlooking this 49-acre body of water that provides year-round fishing for bass, catfish, bluegill, and sunfish, and in colder weather, for stocked trout. Lower Thumb Rock is located along a seasonal stream that flows into the lake at the base of the hill topped by Upper Thumb Rock.

Eash area has tables sheltered by ramadas, and each has its own restrooms. A set of stone steps leads down to the shore from Upper thumb Rock which is the more open of the two areas. Lower Thumb Rock is more sheltered than its hilltop neighbor and provides access to the lake via a short trail that is barrier-free. The public boat launching ramp is only a short distance away as well.

Though these two lakeside picnic areas are open year-round, the 4,000-foot elevation of the area means that the weather can be quite cool here during the winter and early spring. That may come as a surprise since the Mexico is only a few miles away, but cool weather makes the trout fishing better and since the area is so much less crowded when it is cool, that may be the best time to visit.

LOCATION: 68 miles south of Tucson and 17 miles northwest of Nogales.


  • Turn west off of l-l9 approximately 8 miles north of Nogales at the Peña Blanca/Ruby Road (AZ Highway 289) Exit 12.
  • Follow the road west about 9 miles to Peña Blanca Lake.
  • Turn right (north) on the paved road that leads to the lake and drive about 0.5 miles to the picnic area parking lot.

ELEVATION: 4,000 feet.



  • Close to the Lake
  • l2 sites in Upper Thumb Rock Area
  • 7 sites in Lower Thumb Rock Area
  • Access to the lakeside trail
  • Good views of the lake (Upper Thumb Rock)
  • Tables,fire grills, toilets (some barrier-free)
  • Paved access
  • No water

FEE: None


  • No trailers allowed
  • Pets must be on a leash
  • No overnight camping
  • Pack and saddle stock are not permitted in picnic area
  • Firewood is not available. Bring your own wood or bring charcoal or a camp stove for cooking.
  • Nearest Medical facilities and additional supplies in Nogales
  • There is a paved boat launch ramp at the lake. Only electric trolling motors are permitted.
  • A valid Arizona Game & Fish license is required. Arizona Game & Fish Department rules and regulations apply.