South River Peak is a 13,154-foot summit in Colorado’s San Juan Mountains, within the Weminuche Wilderness of the Rio Grande National Forest. Rising in a remote alpine landscape of broad basins and rugged volcanic peaks, it was historically known as Macomb Peak, with the name South River Peak in use by 1906 during an era of increasing federal mapmaking and forest administration in the West. The summit has a severe alpine climate classified as Köppen ET, with no weather station at the top, while the nearby Middle Creek SNOTEL station on its northern flank records subarctic conditions. The peak remains valued for its isolation and protected wilderness setting.