The medieval dock was found next to a fallen Roman wall
An archaeological dig at a Kent fort has uncovered the coastline at the time of the Roman invasion of Britain in 43AD - two miles from today's shore.
The team was excavating a 295ft (90m) stretch of collapsed Roman wall, when they found a small medieval dock.
English Heritage archaeologist Tony Wilmott said they then found a "hard surface", in a water-filled trench, which was the Roman beach.
The dig was on previously untouched land at Richborough Roman Fort.
Mr Wilmott said: "It is widely known that Richborough Roman Fort was the gateway to Roman Britain 2,000 years ago.
"But what is really exciting is that we have actually found the Roman foreshore while digging in a deep trench alongside the remains of a Roman wall.
"The bottom of the trench continually fills with water and by trowelling you can feel the hard surface, which was the Roman beach."
He added: "We have long been curious about this fallen Roman fort wall and now we know there was a Roman harbour sitting out there."
Smaller finds included Roman coins and fragments of decorated marble
At the start of the dig, local volunteers helped to reclaim the walls from undergrowth, exposing them for the first time since the 1930s.
Archaeologists also uncovered a number of smaller finds such as Roman coins and fragments of Italian marble believed to be from a great triumphal arch built at Richborough in about 80AD to commemorate the Conquest of Britain.
Mr Wilmott said the Roman coastline was the original shore at the time of the Roman invasion of Britain in 43AD.
He said the significance of the medieval quayside was still being evaluated but it was known that Sandwich was once a large medieval port.
In the Roman era, Richborough Roman Fort overlooked a sheltered lagoon, where the invading Roman forces first landed.