The Cambridge Archaeological Unit (CAU) conducted a trial trench evaluation over the entire proposed quarry area in 2003, following geophysics and a transcription of aerial photographs. This revealed an early bronze Age ring ditch, large area of Middle Iron Age settlement and field systems, three Roman-era settlements and Anglo-Saxon activity. The areas containing the Roman and Anglo-Saxon activity were excluded from the extraction area, and the archaeological investigations focused on prehistoric archaeology. Excavation was undertaken in 2007, 2011 and 2012. They uncovered a substantial Middle Iron Age settlement, with several phases of enclosures apparent along with many hundreds of pits – including several hundred grain storage pits. The settlement is one of the largest of its kind, and was occupied for around 200 years from c.400 BC to c.200 BC.