 These casks were pulled along the road by slaves and later oxen before this method of freight transportation was made obsolete by the introduction of sturdy wagons.The rolling road in western Baltimore County connecting Rockdale with Elkridge, which was likely built in 1714 by William Summers, is the only such road in Maryland whose name survived to modern times.South Rolling Road was improved as a macadam road from Washington Boulevard (later US 1) to Frederick Road (later US 40 and now MD 144) by 1921.