When Was the Last Eruption of Mount Hood?
Mount Hood photographed from the International Space Station in 2009. Image: NASA, ISS020-E-28123. NASA image and explanation.
Reviewed September 10, 2026 · Mount Hood Stories
The U.S. Geological Survey lists 1865 as Mount Hood’s most recent eruption. Its youngest major eruptive period, called the Old Maid period, began around 1781. Those dates describe different parts of the mountain’s history, which is why both appear in answers to this question.
Why do some sources say 1781?
According to the USGS eruption history, the Old Maid period involved lava-dome growth, pyroclastic flows and lahars. It lasted a decade or more. Crater Rock, high on the south side of the mountain, is a remnant of the dome formed during that period.
This was the most recent major episode to leave substantial deposits. It is more useful to describe it as an eruptive period beginning around 1781 than as a single eruption on a precisely known day.
What happened in 1865?
USGS discusses eyewitness reports of activity in 1859 and 1865 and notes that no deposits have been unequivocally linked to those reported events. Its volcano overview nevertheless lists 1865 as the most recent eruption.
The distinction matters: the date in a volcano summary and the age of the youngest major deposits are not necessarily the same. An account of a small historical event should not be illustrated or described as though it were a documented, mountain-destroying explosion.
The quick answer: 1865 is the most recent eruption listed by USGS; around 1781 marks the start of Mount Hood’s youngest major eruptive period.
Is Mount Hood still an active volcano?
Yes. Mount Hood is an active volcano with a geological record extending back hundreds of thousands of years. Long quiet intervals do not mean that a volcano is extinct, and past intervals do not create a dependable countdown to its next eruption.
USGS describes potential future hazards including lava-dome growth, pyroclastic flows and lahars—fast-moving mixtures of water, mud and volcanic debris. River valleys such as the Sandy and White can channel volcanic debris far beyond the upper mountain. Its hazard information and maps explain the geography more clearly than a blanket statement that the entire region faces the same risk.
Do earthquakes mean an eruption is coming?
Not by themselves. USGS reports that much of the seismicity around Mount Hood is associated with regional tectonic processes. A list of nearby earthquakes cannot establish that magma is rising or predict an eruption.
For the current volcano status, use the official USGS Mount Hood page. Our Hood Hub: Mount Hood weather and official reports brings together mountain information and official-report links, but an earthquake feed is not an eruption forecast.
What should visitors check?
Separate long-term geology from today’s travel decisions. Read official volcano notices, then check the weather, roads and any Forest Service closures for your actual destination. A historic eruption date cannot tell you whether a trail or road is open this weekend.
