1. The first post office in Yellowstone National Park was established in 1887 on July 23rd. Located in the Mammoth Hot Springs area, it served as a vital communication link between park rangers and the outside world.

2. Wyoming's first oil well was drilled on July 23, 1884. It was located in Fetterman, a small town in northeast Wyoming, and ushered in a new era of oil production for the state.

3. On July 23, 1903, Wyoming's first canal system for irrigating farmlands was completed. This system helped to transform Wyoming from a primarily grazing and mining economy to a more diversified agricultural economy.

4. Wyoming became the 44th state to join the Union on July 23, 1890. It was the first state to give women the right to vote, and its state motto, "Equality State," reflects this history.

5. The world's largest single-mineral hot spring, located in the Thermopolis area of Wyoming, was first discovered on July 23, 1900. The spring - which produces 3.6 million gallons of water per day at a constant temperature of 135 degrees Fahrenheit - has become a popular tourist attraction.