The parcels of land at Clay Hill described in the River House deeds are in the shape of an inverted triangle with (on present day references) the northern perimeter extending from the Ash path east along the north side of Devonshire Hill Lane continuing down Mayfair Gardens to the Great Cambridge Road, turning south to the junction with Compton Crescent then bearing north west following Compton Crescent (the original route of White Hart Lane), past Piper's Court, alongside the Ash path meeting again with the northern perimeter.