Jefferson County Oklahoma has 6 places on the National Register of Historic Places including 2 places of Statewide significance. Significant places include San Bernardo and State Highway 79 Bridge at the Red River, First Presbyterian Church, Irving Baptist Church and Jefferson County Courthouse. 
Some of the country's most noteable architects helped create the Jefferson County places including  Rock Island & Pacific RR Co Chicago,  J.B. Osborn,  J.C. Berry, Layton,Hicks and & Forsyth. Prominent architectural styles found in Jefferson Country are Art Deco, Gothic Revival and  Tudor Revival.