1. The Colorado State Capitol, located in Denver, was completed on August 12, 1908. The building, which took 14 years to construct, is made of Colorado white granite and features a distinctive gold dome.

2. On August 12, 1893, the Denver and Rio Grande Western Railroad completed construction of the Alpine Tunnel, located in the Rocky Mountains. It was the highest railroad tunnel in North America, but was closed in 1910 due to safety concerns.

3. In 1933, the town of Pueblo experienced a catastrophic flood on August 12, known as the "Arkansas Valley Disaster." The flood caused extensive damage and resulted in the deaths of over 100 people.

4. On August 12, 1867, the town of Colorado Springs was officially incorporated. It was founded just two years prior by General William Jackson Palmer as a resort town and was named for the nearby Pikes Peak.

5. The Colorado State Fair, which takes place annually in Pueblo, begins on the Friday before August 12 and runs for ten days. The fair includes livestock shows, carnival rides, and a variety of exhibits showcasing Colorado agriculture and culture.