Cincinnati Observatory on Mount Lookout is the oldest professional observatory in the United States and still serves both research and public astronomy. Founded under Ormsby M. Mitchel, it began on Mount Ida, where Nicholas Longworth donated land and John Quincy Adams gave his last public speech at the 1843 cornerstone ceremony; the hill was later renamed Mount Adams in his honor. Its 1845 Merz und Mahler 11-inch refractor was the nation’s largest telescope in the early 1840s. After coming under the University of Cincinnati in 1871, the observatory moved in 1873 to escape city smoke and grew into a major center for astronomical research, education, and outreach.