Fodor's Expert Review Devonshire Royal Hospital
This impressive 18th-century building was designed by John Carr as a stable with room for 110 horses. In 1859, the circular area for exercising horses was covered with a massive 156-foot-wide slate-color dome—bigger than that of St. Paul's Cathedral in London—and incorporated into a hospital. The University of Derby has taken over the building, and visitors can access it for free when school is in session.