Report on a magnetometry survey, conducted to inform the proposed construction of a new poultry development on land at High Dike, Great Ponton. Traces of medieval ridge and furrow were noted across much of the surveyed field as blocks of parallel linear magnetic anomalies, along with a small number of possible pit-like anomalies, located towards the northern edge of the site. Subsequent trial trenching in this area resolved the pit-like anomalies towards the northern edge of the site as a mixture of geological features and modern disturbance (see ELI13470).