The first county courthouse was a log house in Warrenton that belonged to (and was occupied by) Enoch Farmer, one of the county's earliest settlers. When the county seat moved to Williamsport, a log house belonging to the town's founder, William Harrison, served this purpose for several years. The first purpose-built courthouse was completed in 1835 at a cost of $2,000; in 1872, it was replaced with a new building that cost $48,000. The third courthouse was built in 1886, in a new section of town that grew around the newly constructed railroad. That building burned in 1907, and the fourth and current Warren County courthouse was completed on the same site in 1908 at a cost of $115,000.