Mt Ida, Historic house in Ellicott City, Maryland, United States

Mt Ida is a historic home in Ellicott City, Howard County, Maryland, built in 1828 for William Ellicott, grandson of founding brother Andrew Ellicott. The builder was Charles Timanus, also principal builder of the neighboring Patapsco Female Institute and the Howard County Courthouse.

Mt Ida was built in 1828 for William Ellicott, grandson of city founder Andrew Ellicott, by builder Charles Timanus, who also worked on the Patapsco Female Institute and the Howard County Courthouse. Judge John Snowden Tyson and his family lived there from the 1850s; his daughter Ida Tyson, the mansion's namesake, stayed until she was 90 in the 1920s. Ownership later passed to John Ward Wilson, and in 1972 Commissioner Charles E. Miller sought to rezone the property for offices; as of 2013 it belonged to the Miller Land Company.

The mansion's name comes from Ida Tyson, daughter of Judge John Snowden Tyson, who lived there until she was 90 in the 1920s. The Tyson family occupied the house from the 1850s, and later owners included John Ward Wilson and Commissioner Charles E. Miller.

Mt Ida stands on a hillside site in Ellicott City, Howard County, Maryland, and is a private residence rather than a public building, so there are no set visiting hours or on-site staff. The house is best seen from the public road; the grounds themselves are not open to walkers. The 1972 rezoning attempt by Commissioner Charles E. Miller, which would have turned the mansion into offices, was not carried through, and the property remained with the Miller Land Company as of 2013.

The mansion's name comes from Ida Tyson, daughter of Judge John Snowden Tyson, who lived there until she was 90 in the 1920s. In 1972 Commissioner Charles E. Miller tried to rezone the property to turn it into office buildings; as of 2013 it belonged to the Miller Land Company.