Before revision: The tar was modified by adding small amounts of Portland cement, resin, and pitch.Hooley, E. Purnell, , "Apparatus for the preparation of tar macadam", July 26, 1904 The Italian Autostrada dei Laghi ("Lakes Motorway"; now parts of the Autostrada A8 and the Autostrada A9), the first controlled-access highway ever built in the world, in 1925, a year after its inauguration.
After revision: The tar was modified by adding small amounts of Portland cement, resin, and pitch.Hooley, E. Purnell, , "Apparatus for the preparation of tar macadam", July 26, 1904 The Italian Autostrada dei Laghi ("Lakes Motorway"; now parts of the Autostrada A8 and the Autostrada A9), the first controlled-access highway ever built in the world, in 1925, the year following its inauguration.