Weakley was also a co-founder of the town of Jefferson in Rutherford County, Tennessee. He and Thomas Bedford, a fellow land speculator, were granted as assignees a North Carolina land grant and had laid out 102 town lots and a Public Square by 1803, at the junction of the East and West Forks of the Stones River. The town of Jefferson was the first county seat of government for Rutherford County, and contributed immensely to the early economic development of the area during the first decade after its formation. The Stones River provided for direct access for goods and commodities such as timber and other cash crops to be shipped by flat boat to the Cumberland River and Nashville and thereby to far away ports such as New Orleans, Pittsburg, and beyond.