3.5 mi of trail, end to end · Hike the San Antonio Mountain Trail: 11 mi round trip in the Service's write-up · about 1,000 ft of climbing · 8,904 ft–9,910 ft · native surface · bike, hiking, horse · seasonal: Winter seasonal closure dependent on current conditions
TrailheadsCerro Seco Trailhead 8,897 ft Drive there · San Antonio Mountain Trailhead 8,902 ft Drive there
Hike the San Antonio Mountain Trail 11 mi round trip · the Park Service's write-up
5-6 Hours · no dogs · entrance fee applies · reservation required · Spring, Summer, Fall · season The backcountry is closed to vehicular traffic from November 15 - May 14.
Start San Antonio Mountain Trail
The San Antonio Mountain Trailhead sign. Photo: NPS
This strenuous, 11-mile (17.7 km) out-and-back trail heads south from Valle San Antonio, up a narrow drainage, and then steadily climbs as it passes through several beautiful glades before terminating just below the summit of San Antonio Mountain. Good opportunities for wildflowers, especially in spring and fall.
Elevation: 8,394 - 9,922 feet
Accessibility This unpaved, natural surface trail has steep grades. Service animals permitted.
The lines are the National Park Service's public trails layer, the trailheads and the waterfalls, views, peaks and historic places along them the Service's public points of interest, read 2026-10-16 and simplified for the map; the length is the line's, end to end. The write-ups are the Service's own "things to do" text, unedited. Heights come from USGS 3DEP through Terrain Tiles on AWS (Mapzen/Tilezen), read along each line and rounded; a short trail on steep ground can be off by a few tens of feet. Closures change: check the park's own site before you go.
