Mill Hill was once buried in an ancient forest that covered most of Middlesex, Herts & Essex. The local remains of that forest being Scratchwood, which was hunted in up to the 1920's and became an Open Space. By the early 18th century estates had been formed and large houses built, many of which exist today, – Rosebank, Littleberries, Jeannettes, Highwood House, Holcombe House, and others. The staffing of houses and estate management attracted additional workers to the area. There were many farms – Bittacy, Bunns, Burton Hole, Daw's, Dollis, Goldbeater's, Lawrence, Mote End, Uphill, and others. These almost all disappeared under housing or other developments.
Firstly, many institutions acquired land along the Ridgeway which they managed to retain, including a Nonconformist School – now Mill Hill School. Secondly, with road system improvements and the arrival of the railways in 1867, there was a huge impact on the accessibility of Mill Hill. Thirdly, there was a house building explosion fuelled by this new easy access into London, initially in the Poet's Corner and Mill Hill East areas.
Mill Hill took on the form we recognise. The focal point moved away from the village to the lowlands west of the Ridgeway. The construction of the Barnet Bypass in 1926 - the A1/A41 - removed some shops and houses and more commercial activity sprung up at the lower end of Lawrence Street, which was renamed The Broadway. Some estates built in this period were 'Mill Hill Garden Village' (Goodwyn & Newcombe Park) and Uphill Farm Estate.
The imposition of the Green Belt in 1939 restricted continued house building but after the 2nd World War building resumed. By 1949 residents found the threatened loss of green space unacceptable and the Mill Hill Preservation Society was formed by the first Chairman of the Society - Mr Ivar Gunn. The M1 Motorway (1967) made little difference to Mill Hill. By now much of Mill Hill had developed into an outer London suburb typical of others on the fringes of London. It differs, however, in the retention of large properties in green space still in agricultural or institutional use, which makes it a highly desirable place in which to live and work.