The only very rugged part of the route is in crossing the Big Horn mountain, which is about 30 miles wide.
William Henry AshleyThe snow continues with high winds we remain at this camp to day in consequence of the weather.
William Henry AshleyAfter an unremitting and severe labour of two days, we returned to our old encampment with the loss of some of my horses, and my men excessively fatigued.
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 Ashley