Coordinates: 51°17′47″N 1°19′09″E / 51.2965°N 1.3192°E / 51.2965; 1.3192

Richborough ( /ˈrɪtʃbᵊrə/) is 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 Isle of Thanet from the mainland.

The channel has now silted up; prior to this, Richborough was an important natural harbour and was the landing place of the Roman invasion of Britain in AD 43. Until October 2008 there was uncertainty whether this was the site of the Claudian invasion of Britain; two ditches at the site which have been dated to the Roman period were interpreted as defensive structures, however some archaeologists had favoured the theory that the landing took place in the vicinity of modern-day Chichester. The 2008 discovery proved that this was a defensive site of a Roman beachhead, protecting 700 metres of coast.