John Ruan House

Ruan Mostert House
John Ruan House, from the southwest
Location4278–4280 Griscom St.,
Philadelphia, Pennsylvania
Coordinates40°0′36″N 75°5′28″W / 40.01000°N 75.09111°W / 40.01000; -75.09111
Built1796
Architectural styleGeorgian
NRHP reference No.85003410
Significant dates
Added to NRHPOctober 31, 1985
Designated No parameterJanuary 3, 1985

John Ruan House (1794) is a historic mansion located in the Frankford section of Philadelphia, Pennsylvania, United States. It housed the Grand Army of the Republic Civil War Museum and Library from 1958 to 2021.

The building was added to the National Register of Historic Places in 1985, and to the Philadelphia Register of Historic Places that same year.