The Nuttalls were the first attempt to list, on consistent objective rules, every true mountain in England and Wales. John and Anne Nuttall defined a mountain as a summit at least 2,000 feet (610 m) high with a drop of at least 15 m (about 50 ft) on all sides — a measurable test of both height and prominence — and their two-volume survey, The Mountains of England and Wales (Wales 1989, England 1990), catalogued 442 of them. Unlike the guidebook rounds, the list spans the whole country, from Snowdonia to the Pennines; shown here are only the Lakeland Nuttalls. The books are noted for John's fine pen-and-ink drawings and remain a standard reference, kept current through later editions.