Delphi City Hall, also known as the Assian-Ruffing Building and Old City Hall-Opera House, is a historic city hall located at 105-109 Washington Street in Delphi, Indiana. It was built in 1865, and is a three-story, Italianate style red brick building. The third floor was remodeled for use as an opera house in 1881. The building was damaged by a fire in December 1914 and the third floor has remained vacant since.