Hell's Half Acre lava field is a lava plain located on the Snake River Plain, about 25 miles from Idaho Falls. This huge 2,000-year-old plain of hard lava flow is full of large open cracks, sharp jagged rocks, and other obstacles. The 68,760 acres of the site southeast of the National Natural Landmark has been declared a wilderness study area.

The site is popular with hikers and there are two trails marked by flags: A short half-hour one and a longer one that requires a whole day and which leads to the central volcanic vent – a dark, low hill, about 700 feet long and almost 200 feet wide. This is the spot where the lava broke through the surface of the land thousands of years ago. About half way along the trail is a gazebo and a lovely scenic overlook.

If you come in the spring, you will notice clumps of wild flowers, bright green lichens, and mosses, starkly contrasting with the dark volcanic rocks.

Address: Interstate 15, Mile Marker 101 on I-15, Idaho Falls, ID 83221

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