This is the net-downhill desert race people name when they want a fast December marathon. You ride a bus up to Biosphere 2 outside Oracle, start at 7:15 as the light comes over the Santa Catalina Mountains, and run back toward town along Oracle Road with those mountains on your left the whole way, through Catalina and Oro Valley to the finish at Pima Community College's Northwest Campus. The course sheds roughly 1,500 feet with under 300 feet of climbing, and after the 2025 adjustments it counts for Boston with no downhill penalty. The start sits well above the finish, so the first miles feel sharply colder than the last; bring a layer you can drop. Aravaipa Running now organizes the event, which has been held since 1969. The long highway stretches are honest about what they are, with 15 aid stations and a 7.5-hour limit.
Net-downhill point-to-point from Biosphere 2 near Oracle down Oracle Road/SR 77 along the foothills of the Santa Catalina Mountains through Catalina and Oro Valley to Pima Community College Northwest Campus, with some rolling hills early and long highway stretches. Course map ↗
Closes 2026-12-12. Open on 2026-10-14 via RaceRoster; deadline December 12, 2026 at 6:00 PM MT. Price tiers: Sep 1-Nov 14 marathon $180.79 (incl. fees), Nov 15-Dec 12 $195.95; half $159.15/$174.30; 50K $191.63/$206.78; 4-person relay $325.85/$347.51, relay limited to 60 teams. RaceRoster shows the earliest price tier beginning December 19 (year not stated). RaceRoster displayed 2,270 participants registered across all events on 2026-10-14. Register ↗
- Organizer Aravaipa Running describes the event as 'net downhill courses along the foothills of the Santa Catalina mountains run since 1969'; the marathon drops 1,493 ft against 292 ft of gain. ↗
- The course is USATF certified and a Boston Marathon qualifier; the 2025 course was adjusted so finishers incur no time penalty under the B.A.A.'s net-downhill standards. ↗
- Find My Marathon ranks it the 8th-fastest marathon course nationally and 1st in Arizona, with 17.3% of 2025 finishers hitting a Boston-qualifying time. ↗
- Marathon finishers grew from 549 in 2022 to 1,125 in 2025. ↗
- There are 15 aid stations on the marathon course, and all distances have a 7.5-hour limit with the course closing by 3:00 PM. ↗
Checked 2026-10-14. Always confirm on the official site before booking travel.