The first Saxon settlements were quite generally on the line of the
old Roman roads. They were surrounded by a rampart of earth set with
a thick hedge or with rows of sharp stakes. Outside this was a deep
ditch. These places were called towns,[1] from "tun," meaning a fence
or hedge. The chief fortified towns were called "burghs" or
boroughs. Later on, this class of towns generally had a corporate
form of government, and eventually they sent representatives to
Parliament (S213).
[1] One or more houses might constitute a town. A single farmhouse is
still so called in Scotland.