The tramway was the third section of tramway constructed for Middlesex County Council. It was intended to serve the rapidly-growing population settled along the Great North Road between Highgate and Finchley.
The line started underneath Highgate Archway; this spot was chosen as it was on the boundary between the districts of the London County Council and the Middlesex County Council. It ran via Highgate railway station to the boundary of Hornsey parish and thence through the area of Finchley Urban District Council to Whetstone.