Roberts, Idaho · Bonneville County · Facility
These undeveloped trails offer scenic solitude; there is a short 0.5 mile loop trail and a 4.5 mile trail to the main vent of the Hell's Half Acre flow. Trail routes are marked with poles across lava. A picnic area, fire ring and portable toilets are located at the trail-head. This is treacherous rocky terrain and prop…
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These undeveloped trails offer scenic solitude; there is a short 0.5 mile loop trail and a 4.5 mile trail to the main vent of the Hell's Half Acre flow. Trail routes are marked with poles across lava. A picnic area, fire ring and portable toilets are located at the trail-head. This is treacherous rocky terrain and proper footwear is advised. It also gets very hot and there is little to no shade so proper sun protection and water is advised.
From Idaho Falls, travel west on Highway 20 to mile marker 287. Continue 0.3 miles until you see a sign for "Lava Trail." Turn left onto the gravel road (staying left at the fork) and continue one-quarter mile to the trailhead.
Driving directions (Google Maps) →Heading to Twenty Mile Trail? A few things to know before you go:
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