Architect: Charles Holden, 1926. Northern Line Built by Holden as one of seven stations extending the Northern Line from Clapham Common to Morden. Holden used a standard design of plain Portland stone and glazing for the frontage, that could be adapted to the shape of a particular site. In the case of Tooting Bec, one entrance was an island site, with the sides almost parallel to each other, whereas the other was a corner site. The pole mounted roundels were a feature of all these stations.