The new culture of the Anglo-Saxons replaced the culture of the Romans and ancient Britons. The number of Brittonic place names in this area is extremely low. Though the first written record of most of the place names in the county is the 11th-century Domesday Book, most were coined at a much earlier date. Places with names ending in "-ham" in Norfolk (but not those ending "-ingham") are generally sited favourably by rivers or near fertile soil and grew in importance from large vills into the county's modern market towns. Comparatively less important settlements tended to end with the suffixes "-ton", "-wick" or "-stead". Excavations and place-name evidence indicates that the early Anglo-Saxons (pre-800 AD) seem to have occupied the south and south-west of Norfolk most densely, with settlements concentrated along river systems. A settlement and a cemetery at Spong Hill, containing both graves and inhumation pots, is an example of one of the earliest Anglo-Saxon sites to have been found in Norfolk. During the 7th century East Anglia adopted Christianity and the custom of burying grave goods, found at numerous sites, eventually ceased. Evidence of early Anglo-Saxon settlement exists in the form of Ipswich ware pottery and coins ("sceattas") that are unique to the period.