General Stephen Kearny along with Kit Carson and the rest of his small army that escaped the Battle of San Pasqual routed a small band of Mexicans from here killing or wounding five.  They used the hill as a fortification waiting for help from San Diego while they were surrounded by Mexicans.  Kit Carson carefully walked through the enemy lines at night along with two other men and made his way to San Diego where he sought help for the entrapped Kearny.  They returned with more than 100 men to save Kearny.  The hill was called Mule Hill because they were so low on food that they ate some of their mules.  The rock enclaves they constructed can still be seen today and there is a monument on the hill which reads (note that the monument set up in the 1950s is probably misplaced.  A study in the 1970s found the site on another location -- see the reference given here.  Ask for directions for the new site at the San Pasqual State Park): "On December 7, 1846, day following Battle of San Pasqual fought five miles east of here, General Stephen Kearny’s command while marching on San Diego was attacked by Californians. The Americans counter-attacked, occupied hill until December 11 when march was resumed. Short of food, they ate mule meat and named the place “Mule Hill.”