 For the introduction of London Underground services , the original station was completely demolished and rebuilt . The station was provided with two additional platforms , giving four in total . The platforms comprise two parallel islands with tracks on both sides . This was necessary as the intention of the Northern Heights project was that trains would be able to run south from East Finchley to Highgate via both the surface and the underground routes . The inner pair of tracks served the surface route , whilst the outer pair serve the tunnel route . 
