Asa Johnston Farmhouse, Historic farmhouse in Johnsonville, Alabama.

The Asa Johnston Farmhouse is a 19th-century residential building in Alabama with symmetrical doors and windows across its front. The structure includes a porch, a central open passage, and a separate dining room connected by an elevated covered walkway.

Ezra Plumb, a carpenter from Connecticut who settled in the area around 1835, built the house in 1842 for Asa Johnston. Johnston had reached Conecuh County by 1818, the year it was founded, and by 1860 held 3,450 acres valued at $10,000 and 67 enslaved people. The house was listed on the Alabama Register on October 4, 1993, and on the National Register on May 21, 2008.

The house displays features of early American rural architecture, with crafted details that show how wealthy Southern landowners lived during this period. The central open passage reflects the climate and lifestyle needs of that era.

Visiting requires arriving by car since the building sits in a rural area. Plan to spend time walking around the structure to observe all the exterior details and layout.

The central passage features a barrel-vaulted ceiling that is rarely seen in American residences from this time. This detail is uncommon for the region and shows skilled craftsmanship in ceiling design.