[1][2] Radiocarbon dating of organic sediments has showed that the cutting of the ditch must have occurred prior to 395 to 205 cal BC.

[7] In 1975 retired geologist and researcher Christian O'Brien suggested that Portingbury Hills had a purpose in archaeoastronomy and was constructed in the Bronze Age which gave it some brief coverage in the Sunday Telegraph.

O'Brien suggested that the mound was aligned astronomically with Wandlebury Hill via a series of equally spaced, hand-carved, stone monoliths forming a Loxodrome.

[9] Glyn Daniel, Professor of Archaeology at Cambridge University dismissed the paper as "nonsense" and Alexander Thom could find nothing in it to revise the prevailing view of Wandlebury as an Iron Age fort.

Archie Roy, Professor of Astronomy at Glasgow University commented that "in the absence of a more convincing explanation, this conclusion also has to be taken very seriously.” [10][11]