"Massacre Rocks was a well-known site on the Oregon Trail and California Trail during the mid-19th century. Immigrants gave the name Massacre Rocks to the trail's narrow passage through the rocks. The name stemmed from the fear of a possible ambush by Indians." https://www.u-s-history.com/pages/h2591.html
Alleged Indians massacred folks in a few wagon trains on the Oregon Trail. More Indians than white folks died.
It's the commercial name given to the area to reflect the attacks on 2 wagon trains in August, 1862. 10 immigrants were killed.
The site sits along the old Oregon trail. Lots of history in the area.
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