Sight · Katmai National Park
Remote stratovolcano with active fumaroles and serious backcountry commitment
Overview
Mount Griggs is a remote, andesitic stratovolcano rising above the Valley of Ten Thousand Smokes. It’s the tallest cone in the local cluster and sits roughly north of Novarupta, making it a magnet for geology-minded hikers and mountaineers who don’t mind big effort for big solitude. There’s no trailhead, no signage, and no services—this is pure Katmai wilderness.
Griggs has a truncated summit with three concentric craters, the outer one breached to the southwest. A collapse in the early Holocene produced a broad amphitheater and a debris avalanche on the west–southwest flank; later andesite flows partly refilled the summit depression. Construction of the cone spanned roughly 85,000–10,000 years through overlapping lava flows, and unlike some neighbors, Griggs is known for small-volume effusive activity rather than big ash-producing blasts.
Parkwolf’s verdictGeology & What Makes It UniqueMap
Local know-how
Stage from Brooks Camp and use the Valley of Ten Thousand Smokes bus before heading out on foot.
Bring glacier gear and know how to assess crevasses, rockfall, and unstable fumarolic ground.
Carry all water treatment, food, and navigation—there are no services beyond Brooks Camp.
Coordinate your plan and current conditions with the park before committing to the route.
Give bears plenty of space and be prepared to yield corridors they are using.
Plan your stop
The highest, rockiest slopes around here are a summer buffet for grizzly bears.
Katmai Tour Guide
Parkwolf is a GPS audio tour guide for Katmai National Park. As you drive, it chimes in with what’s ahead: hidden gems, upcoming stops, history, geology, and wildlife, right through your car’s speakers.
“Fantastic app with many points of information… It’s great to just turn on while you’re driving and it gives you an audio tour of the national Park. We love it!!!!”
Guide
Griggs didn’t erupt in 1912, but its slopes were smothered in the fallout from the Novarupta event that created the Valley of Ten Thousand Smokes and collapsed nearby Mount Katmai. It remains one of the fumarolically active cones in this exceptionally dense volcanic cluster along the Aleutian arc.
This objective is only for experienced, self-sufficient backcountry travelers with mountaineering and glacier travel skills. Hazards include crevasses, rock and ice fall, volatile weather, active fumaroles (toxic gases, unstable hot ground), river crossings, and very limited rescue options. Brown bears use the same corridors you will—expect encounters and follow best practices.
What you’ll notice today is that the volcano is very much alive: hot, SO₂-rich fumaroles near the summit vent at near-boiling temperatures and can even be heard from the valley floor in calm conditions. Expect sulfur deposits and unstable, hot ground around vents.
Wildlife
752 sightingsBrown BearMost seen around 7 PMSighting map
55 sightingsSockeye SalmonMost seen around 11 AMSighting map
15 sightingsWolfMost seen around 9 PMSighting map
68 sightingsBald EagleMost seen around 5 PMSighting map
17 sightingsMooseMost seen around 6 AMSighting map
19 sightingsBelted KingfisherMost seen around 7 AMSighting mapSighting maps show where each species has been reported across Katmai. Wildlife moves, so no sighting is guaranteed.
Parkwolf’s Katmai ranking
The audio tour guide for the drive, plus offline maps, trails, and wildlife heatmaps for when the signal drops.
