Christopher and John Greenwood state in the title that the plan was made from an “Actual Survey”, which had taken three years. Plans at the time were often copied from older surveys, or re-issued with minor updating; so conducting a new survey was indeed something to boast about. The plan, which was finely engraved by James and Josiah Neele, is stylistically similar to the Ordnance Survey maps of the time, although it was engraved on a much larger scale of 8 inches to the mile, compared to the OS one inch to the mile. It includes detailed depictions of streets, houses, public buildings, parks, squares, woods, plantations, rivers, hills, windmills; also the marking of the boundaries of the City of London, Westminster, Southwark, Rules of the King’s Bench & Fleet Prison, Clink Liberty, counties and parishes. Below the plan is a dedication to George IV, which is flanked by views of Westminster Abbey and St Paul’s Cathedral.

The maps by Christopher and John Greenwood set new standards for large-scale surveys. Although they were unsuccessful in their stated aim to map all the counties of England and Wales it is probably no coincidence that of the ones they missed, Buckinghamshire, Cambridgeshire, Herefordshire, Hertfordshire, Norfolk and Oxfordshire, all except Cambridgeshire were mapped by Andrew Bryant in a similar style and at the same period. From a technical point of view the Greenwoods’ productions exceeded the high standards set in the previous century though without the decoration and charming title-pieces that typified large scale maps of that period.

The Greenwoods started in 1817 with Lancashire and Yorkshire and by 1831 they had covered 34 counties. Their maps were masterpieces of surveying and engraving techniques, and in view of the speed at which they were completed, their accuracy is remarkable. They mark the boundaries of the counties, hundreds and parishes, churches and chapels, castles and quarries, farmhaouses and gentlemen’s seats, heaths and common land, woods, parliamentary representatives and distances between towns. The price of 3 guineas each compares with the the first edition Ordnance Survey sheets of 7s 6d, though the latter did not relate to complete counties.