Geology of Kent into northern France. The fold arises from the continuing Alpine orogeny and results in the general northward dip of the rock strata in most of Kent. There are extensive spreads of coastal and estuarine alluvium on the Thames Estuary coast, in the low ground surrounding the Isle of Thanet and across Romney Marsh. Alluvium also floors the valleys of the River Medway and Stour. 'Clay-with-flints' is a commonly occurring deposit across the North Downs which is a product of periglacial conditions during the last ice age. Loessic deposists, of aeolian origin i.e. windblown, are common in east Kent, especially on
Kingdom of Kent and Cambridgeshire. Archaeological evidence suggests that at some point in the sixth century, East Kent annexed West Kent. To the south lay the Weald, a dense forest of no value to the Kentish elite, leaving the fertile area west of the kingdom attractive for conquest, particularly the Darenth Valley and the dip slopes of the North Downs to the west of the Medway. Firmly in the control of an elite class, Kent is the first Anglo-Saxon kingdom to appear in the historical record in 597. The monk Bede refers to Kent as ruled by Æthelberht at this period, making him