This marks the Southwest corner of the Fort, built in October and November 1851 as protection from Indians, by first 17 families under direction of Anson Call, Jesse W. Fox, surveyor. About 2 city blocks in size, the front wall 8 to 10 feet high was built of cobblestones, other walls of mud, straw and rocks. The East wall followed the foot hills in circular form. Fort walls were used as back walls of homes. Mail station, Church, School, recreation grounds, gardens, and corral were within and Chalk Creek ran through the Fort.