1. In 1847, on July 21st, a group of Mormon pioneers arrived at the Salt Lake Valley, led by Brigham Young. This event marked the founding of Salt Lake City and the beginning of the settlement of Utah by Mormon pioneers.

2. On July 21, 1955, the first three blocks of the Salt Lake City Transit Authority's new double-tracked trolley system were opened for service. This new system replaced the old streetcar network and provided improved transit service for the growing city.

3. In 1904, on July 21st, Utah Governor Heber M. Wells signed a bill officially creating the Utah State Flag. The flag design was created by a committee of the Daughters of the American Revolution and features a beehive representing industry, a sego lily representing peace, and the state motto "Industry" and "Progress."

4. On July 21, 1983, the first segment of the Legacy Parkway was opened in Davis County, Utah. This scenic parkway provides a safe and efficient route for commuters and tourists alike, while also preserving the natural beauty of the surrounding area.

5. In 1930, on July 21st, the National Forest Reservation Commission created the Ashley National Forest in northeastern Utah. Named after William H. Ashley, an early fur trader and explorer of the area, this forest covers over 1.3 million acres and includes many popular recreational areas such as Flaming Gorge and the Uinta Mountains.