Read this and answer the question

The Anglo-Saxons formed a new, larger, settlement across the Itchen centred on what is now the St Mary's area of the city. The settlement was known as Hamwic, which evolved into Hamtun and then Hampton. Archaeological excavations of this site have uncovered one of the best collections of Saxon artefacts in Europe. It is from this town that the county of Hampshire gets its name.

What river separated Hamwic from the home of previous settlers?
Itchen