1889 Mayoworth Post Office was established on July 16, 1889.
1938 On July 16, 1938, Fort Laramie was declared a National Monument.
1947 The Kortes Dam Post Office was established on this date in 1947. It was named for Mary Kortes who had owned land in the area for many years. The post office was established due to the construction of the Kortes Dam which was started in 1946 and completed in 1951.