It might come as a surprise to some people, but the state of Oregon contains two subglacial volcanoes; tuyas. They are Hayrick Butte and Hogg Rock. They are easy to access, and could potentially represent a great textbook/classroom example of this landform. They are composed of andesite / borderline basaltic andesite lavas. The state of Washington also has a few tuyas but they are less spectacular and harder to access.
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