In 1846, Colonel Alexander Doniphan led 1st Regiment of Missouri mounted volunteers through El Paso del Norte, with victories at the Battle of El Brazito and the Battle of the Sacramento. Then on 7 November 1848, War Department General Order no. 58 ordered the establishment of a post across from El Paso del Norte (now Ciudad Juárez). On 8 September 1849, the garrison party of several companies of the 3rd U.S. Infantry ('The Old Guard', currently the oldest active duty regiment in the US Army), commanded by Major Jefferson Van Horne, found only four small and scattered settlements on the north side of the Rio Grande. The "Post Opposite El Paso del Norte" was first established at the site of Coon's Ranch (often erroneously referred to as Smith's Ranch, now downtown El Paso) and, along with Fort Selden and other Southwestern outposts, protected recently won territory from harassing Apaches and Comanches, provided law and order, and escorted the forty-niners. Van Horne also had nominal command of the Post at San Elizario, the former "Presidio of San Elizario", seventeen miles downstream from El Paso del Norte. With constant Indian raids, garrisons had to be moved frequently to meet the shifting threats. In September 1851, the Post Opposite El Paso and the Post at San Elizario were closed, the soldiers moved north to Fort Fillmore.