The Campus Martius Museum interprets Ohio history. Campus Martius was the second fortification in Marietta, Ohio and the first primarily for civilian defense. The Rufus Putnam House, incorporated in the Museum, is the only remaining part of the fortification. The museum also includes the Ohio Company Land Office. Both are National Register of Historic Places properties. The site is designated as Campus Martius State Memorial. The museum is located a block from the Ohio River Museum. External links Campus Martius Museum - Friends of the Museums Ohio History Connection: Campus Martius References History museums in Ohio Museums in Washington County, Ohio Buildings and structures in Marietta, Ohio Ohio History Connection