| The winterbournes that feed the top of the river include: the main winter stream originating at Uffcott and running through Winterbourne Monkton; the smaller stream flowing at times from Highway Pennings via Yatesbury to join the larger one just west of Avebury; and the tiny stream starting at Beckhampton pond which runs (albeit rarely) along the A4 into the excavation moat around Silbury Hill. The most common definition of the source, however, is near Silbury Hill. Just south of the A4, the river traditionally rose around New Year from the Swallowhead Springs, which emerge from a small wall of chalk at a corner of the meadow. This joins the stream flowing south from Avebury, past Silbury Hill and under the A4. The joined streams then turn east. Half a mile downstream from the Swallowhead Spring, another spring feeds into the Kennet at times from the south end of Waden Hill. At West Kennet the remains were found of a large enclosure of upright tree trunks - a henge - that straddled the river in the early Bronze Age. Further downstream the ancient Ridgeway descends southwards and crosses the River Kennet at East Kennet. | 
