1892 Bartlett Post Office was established on April 29, 1892 in Laramie County prior to the formation of Goshen County. Frank W. Bartlett was the postmaster.1914 The "Park County Enterprise" reported that a "$15,000.00 Carnegie Library grant had been received by Cody. The opening ceremonies for the new Carnegie library were held on the night of May 9, 1916.
1892 Huson Post Office in Sheridan County, was established on April 29, 1892 with Edward W. Huson as postmaster.
1909 Deep Creek Post Office was established on April 29, 1909 in Big Horn County prior to the formation of Washakie County. The post office was located on the west side of Deep Creek.
1899 Dewey Post Office was established on April 28, 1899. Dewey was the location of the Dewey Coal Mine.
1904 Kinkaid Act signed.
1970 On April 28, 1970, Bridger's Pass, Father DeSmet's Prairie Mass Site, Fort Bonneville, Fort Halleck, Fort Reno, and Point of Rocks Stage Station were added to the National Register of Historic Places.
1903 On April 24, 1903, after spending almost two weeks in Yellowstone, President Roosevelt laid a cornerstone for the northern entrance to Yellowstone National Park - today, the resulting structure is known as the Roosevelt Arch.
1868 The first train crossed the Dale Creek Bridge on the Union Pacific Railroad on April 23, 1868. The bridge was a wooden framework structure, 650 feet long and 127 feet high, the largest of its kind on the road.
1907 Raymond Post Office in Big Horn County was established on April 22, 1907 with Charles W. Raymond as its first postmaster.