The only very rugged part of the route is in crossing the Big Horn mountain, which is about 30 miles wide.
William Henry AshleyI had the Big Horn river explored from Wind River mountain to my place of embarkation.
William Henry AshleyWe continued to move forward without loss of time, hoping to be able to reach the wood described by the Indians before all our horses should become exhausted.
William Henry AshleyThese people were well dressed in skins, had some guns, but armed generally with bows and arrows and such other instruments of war as are common among the Indians of the Missouri.
William Henry Ashley