Massacre Rocks State Park
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Massacre Rocks State Park

750+ routes on black basalt — Idaho's best pure sport crag

⚠ Access Notice

⚠️ BLM portion CLOSED as of August 17, 2023. Idaho State Land portion (250+ routes) remains fully open. Always confirm current access before visiting.

About Massacre Rocks

Massacre Rocks offers some of the most varied sport climbing in Idaho: black basalt walls with edges, pockets, blocks, slopers, and cracks rising 30–200 feet above the Snake River Plain. The historic Oregon Trail passed through this gap in the ancient lava flows, and emigrants reported ambush by Shoshone warriors in 1862 — hence the name. Today the atmosphere is considerably more peaceful, with 750+ bolted routes spread across dozens of walls. The rock quality is outstanding — featured, positive holds with just enough friction. Critical note: the BLM portion (approximately 500 routes) has been closed since August 2023. The Idaho State Land portion remains fully open with ~250 routes.

Why Climb Here

  • Best basalt sport climbing in Idaho
  • Bouldering cave with V0–V10 problems
  • Historic Oregon Trail location — interpretive signs throughout
  • Riverside camping on the Snake River
  • Year-round climbing potential on south-facing walls

Area Stats

Routes250+
Grade Range5.8–5.13
Height30–200 ftft
Best SeasonMarch, April, May, September, October, November
Day Use Fee$8/vehicle (Idaho State Park fee)

Getting There

From Boise: 2 hours east via I-86 to Exit 28

I-86 Exit 28 — paved road to state park. Easy access year-round.

Season

Best

March, April, May, September, October, November

Avoid

June, July, August

Summer heat is extreme — sand can burn bare feet. Fall is the best season: cooler temps, few crowds, excellent rock conditions. Sunny winter days can work on south-facing walls.

Massacre Rocks Gear Kit

Everything you need for a day of bolted sport climbing at City of Rocks, Massacre Rocks, or Black Cliffs.

Shop Massacre Rocks Gear at REI →

Lodging Near Massacre Rocks

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