Map sources for the start of the road near Highgate Wood
Local History and Heritage of Barnet
A1000 road Wikipedia
The A1000 is a main road in the United Kingdom, running north from Highgate, north London for approximately 20 miles (32 km) to Welwyn where it joins the A1(M) motorway. It incorporates part of the main medieval route out of London, and runs through Finchley, Whetstone, Chipping Barnet and Monken Hadley. After leaving Greater London, it passes through Potters Bar, then it skirts Brookmans Park and Welham Green before entering Hatfield, after the A1001 road has split. It finally runs through Welwyn Garden City before reaching Welwyn. It was formerly known as the Great North Road (and parts of it still bear this name), or A1, but after a bypass was built in the 1920s it became the A1000 ca. 1954.