The Mark Twain House in Hartford contains 25 rooms.
Designed by New York architect Edward Tuckerman Potter, the Victorian Gothic–style house was built for Samuel Clemens, his wife Olivia, and their family. Construction began in 1873, and the Clemenses moved into the completed home in 1874. The mansion covers about 11,500 square feet across three floors, making it an unusually large and elaborate nineteenth-century residence.
The house included formal entertaining spaces, family bedrooms, servants’ rooms, a conservatory, and a schoolroom. Twain’s third-floor billiards room also served as his private study, where he wrote late at night. He worked on major books there, including The Adventures of Tom Sawyer and Life on the Mississippi.
In 1881, the family renovated the house and hired Louis Comfort Tiffany’s Associated Artists to decorate many public rooms with richly patterned walls and ceilings. Twain lived there from 1874 to 1891. The property later became a house museum and was designated a National Historic Landmark in 1962. The 25-room figure refers to the historic house itself, not the later visitor center.