Richborough 's a settlement north of Sandwich on the east coast of the county of Kent, England. Richborough lies close to the Isle of Thanet. Although now some distance from the sea, Richborough stood at the southern end of the Wantsum Channel from prehistory to the early mediaeval period. The channel provided a safe searoute from the continent to the Thames estuary and separated the island of Thanet from the mainland. The channel has now silted up; prior to this, Richborough was an important n… (More on Richborough)