Left Fork (Subway) Bottom-Up

This is a very strenuous, mostly off-trail canyon hike rather than a maintained path. A wilderness permit is required year-round for Left Fork, and trips are day-use only; groups are limited to 12. Pets are not allowed. The approach starts at Left Fork Trailhead off Kolob Terrace Road, which can close for snow from fall into spring. Check road and park conditions before driving, and do not enter the canyon when rain threatens: a flash flood can turn the creek corridor dangerous quickly.

There is a gravel-surface parking area, but its capacity and fees were not established, and toilet availability was not confirmed. No food service or potable water was found at the trailhead or along the route. Bring what you need for a long day; do not drink untreated stream water, which may contain toxic cyanobacteria.

The first roughly half mile follows a mostly level, maintained path through juniper and pinyon woodland. It then descends a steep, loose slope about 400 feet to the canyon. That short access section is the easiest walking of the day, and the same slope becomes a tiring climb on the way back out.

Beyond the rim, expect substantial route-finding. The route leaves a regular trail and alternates between faint paths along the banks, boulder-hopping, and walking in the stream. Water is often ankle to knee deep; its depth and the usable line change with flow. The first couple of miles feel rough and obstructed. Farther upcanyon, the creek opens onto broader slickrock and cascades.

Several cascades interrupt the creek bed; one is informally known as Archangel Falls. Farther on, two waterfalls around 15 feet high can be bypassed on the right or south side. Wet slabs are extremely slippery, so move carefully and do not treat the bypass as an easy trail. The creek’s red sandstone shelves, pools and tight turns are part of the route, not a marked path beside it.

The lower Subway appears after the creek bends. Close sandstone walls frame a rounded, tube-like undercut, with pools, potholes and water-polished surfaces. This formation is the bottom-up hike’s destination. Continue only as far as conditions and your ability allow: the narrower terrain beyond can involve waist-deep water or swimming as potholes fill. The celebrated slot is near the end of a long approach, so this is a poor choice if you want a short walk to a viewpoint.

The canyon exposes Kayenta sandstone and related mudstone and siltstone laid down by ancient streams. Water has sculpted the smooth shelves, rounded slot and potholes visible along the way. In fall, red and orange maple leaves can stand out against the sandstone. On the return route, two gray boulders partway downcanyon bear dinosaur tracks; look without touching or climbing on them.

Retrace the creek route, then regain the steep 400-foot slope to the trailhead. The junction for the ascent is easy to miss when tired, and hikers are sometimes reported to walk past it; keep a map available and watch for the exit as you descend the canyon. Treat the posted time as a full-day commitment. NPS describes the hike as very strenuous and warns that people get lost every year.