Johnson County Missouri has 22 places on the National Register of Historic Places including 7 places of Statewide significance. Significant places include Camp Shawnee Historic District, Johnson County Courthouse, Montserrat Recreation Demonstration Area Bridge, Montserrat Recreation Demonstration Area Dam and Spillway and Montserrat Recreation Demonstration Area Entrance Portal.
Some of the country's most noteable architects helped create the Johnson County places including WPA, NPS, William S. Matthews, J.W. Layton, John Albert Adams, Bernard (Ben) Pickel, John Newcomer, Lewis L. Saunders, John W. King and William Lowe. Prominent architectural styles found in Johnson Country are Late Victorian, Queen Anne and Collegiate Gothic.