Great Springs Trail Race - Natural Bridge Caverns
San Antonio, United States • 26 Sep 2026
Great Springs Trail Race - Natural Bridge Caverns
This event takes place at Natural Bridge Caverns and uses both underground and surface terrain. The 4 mile, 8 mile, 16 mile and Youth 1 mile races begin with a short cave section before emerging onto trails that run over flowing hills and through wooded areas. The race hub on the surface serves as the main start/finish area and timing point.
Distances offered include:
- 4 miles run
- 8 miles run and ruck
- 16 miles run
- Last Person Standing run and ruck formats
- Youth 1 mile
Last Person Standing competitors run a core 4.1667 mile loop and ruck competitors use a 2.47 mile loop. LPS entrants must complete each loop within one hour to continue; LPS runners receive a Discovery Tour pass and may earn a Hidden Wonders Tour upgrade after the 24th lap. The LPS hub becomes an all-day and overnight gathering with crew space and drop bag areas.
Course markings include orange caution tape, yellow arrows, and many confidence markers; markings have reflectors for dark hours. Chip timing is used; chips are worn on an ankle strap. Pacers are not allowed.
Aid and support: one on-course aid station serves the 16 mile race and a full aid station at the finish/next-lap arch provides day and night food and drinks. The event is cupless; collapsible cups are available for purchase at packet pickup. Leave No Trace rules apply and littering can result in disqualification.
Ruck division rules require mandatory weigh-ins, weights carried on the back (20 lb under 150 lb runners, 30 lb over 150 lb runners), and prohibit trekking poles and sling bags. Drop bag services are not provided on course; crew and drop bag areas are available around the race hub. Visit the organization's website for the most recent information.