McDonald Observatory, in the Davis Mountains near Fort Davis, became a major center of astronomy through William Johnson McDonald’s 1926 bequest to the University of Texas and land donated by Edwin Hockaday Fowlkes. Built on Mount Locke and nearby Mount Fowlkes for their dark, clear skies, it opened in 1939 with the Otto Struve Telescope, then the world’s second largest. Later additions included the Harlan J. Smith Telescope and the Hobby-Eberly Telescope, one of the largest in the world by 2019. The observatory conducts wide-ranging research, including dark energy studies, and also reaches the public through StarDate and extensive visitor programs.