The trail down the western slope of the Sierra from Donner pass had enormous granite boulders and numerous rocky outcrops and steep slopes before passing through Emigrant Gap (California). Here a Historical marker on Interstate 80 reads: The spring of 1845 saw the first covered wagons surmount the Sierra Nevada. They left the valley, ascended to the ridge, and turned westward to old Emigrant Gap, where they were lowered their wagons by ropes to the floor of Bear River (Feather River tributary) Valley. Hundreds of wagons followed before, during, and after the gold rush. This was a hazardous portion of the overland emigrant trail. After getting down off the ridge most emigrants stayed at Bear Valley to rest themselves and their teams and recover before traveling the approximate remaining to Sutter's Fort. This combination of a very steep and difficult ascent and a sharp difficult descent into Bear Valley on a route that terminated far from the gold strike regions all combined to make the Truckee Trail little used after about 1849 when the Carson Trail was developed. The main route quickly became variations of the Carson Trail which was rough but not as difficult as the Truckee Trail and terminated in the main gold digging regions around Placerville, California.