1869 Pine Bluffs Post Office was established as Pine Bluff Post Office on January 13, 1869 with Theodore H. Vail as postmaster.
1874 "An Act to incorporate Laramie City" was approved by Governor J.A. Campbell on December 12, 1873 to "take effect and be in force from and after the 13th day of January, 1874."
1888 Dry Piney Post Office was established on January 13, 1888 in Uinta County prior to the formation of Sublette County.
1888 Killion Post Office was established on January 13, 1888 with Louisa Killion as postmaster.
1899 On January 13, 1899, Senator F.E. Warren, introduced a bill for the military post to be built in Northeast Wyoming. The post was named Fort MacKenzie.