When coming back from South Dakota, I stopped by the Historical Landmark of Independence Rock, WY 2012.

     Independence Rock, located in modern-day Wyoming, was the second big monolith the emigrants came across on their journey from the east.  Many of the pioneers signed the rock with axle grease.

     Independence Rock is what geologists call a “pluton:” a big body of igneous rock (in this case, a granite that is over one billion years old) that cooled slowly under the surface of the earth and then was slowly exposed by erosion of the surface layers.

     It is more than 1.6 km in circumference and stands up to 45 m higher than the surrounding areas. It gets its name from its main function on the trail: travelers who weren’t at Independence Rock by Independence Day were lagging behind, and in danger from possible bad weather in the mountains ahead.

          Located next to the pleasant Sweetwater River, Independence Rock was a popular place for emigrants who had made good time to take a little rest. Many of them carved their names into the wind-polished surface, and today it serves as a historical record book.

     A few kilometers southwest of Independence Rock, emigrants on the Oregon/California/Mormon trail, encountered another major trail landmark: Devil’s Gate. Here, the Sweetwater River has carved a narrow cleft in the granite Sweetwater Rocks that is about 123 m deep and 500 m long. The cleft is 10 m wide at the base but nearly 100 m wide at its top.

     Millions of years ago, sediments from eroding mountains and ash from volcanoes filled the basins between the mountains. Rivers cut indiscriminately though softer sediment and harder rock. One such cut, once the sediment again eroded away, has left Devil’s Gate.

      Pictured above, although the cleft was too narrow for wagons to pass through alongside the river, emigrants frequently stopped to hike around these rocks and carve their names.  By the early 1850s, trading families were running a post at Devil’s Gate and another at nearby Independence Rock. Mostly these were French-speaking men with Shoshone wives and families.

     3.2 km to the northwest of the picture above, nestled at the foot of the Sweetwater rocks, lies Martin’s Cove.  Here Captain Edward Martin’s exhausted company of Mormon handcart emigrants sought shelter from a severe early winter storm in 1856.  The Martin Company, low on provisions and traveling late in the fall, first encountered winter weather in late October near present day Casper.  Of 576 men, women and children, approximately 145 died along the trail before finally reaching Salt Lake City the last day of November.