The Romans first came to Britain in 55BC when there was an invasion lead by Julius Caesar. It did little more than establish a beach head in Kent and enable the capture of a few slaves. A later attempt, again with only a small force in 54BC lead to the establishment of contact with the local tribes, including the Atrebates and the Catuvellauni, and formed some form of client relationship. They were already familiar with the Atrebates having battled with them in Gaul. It was not until 43BC when a large force landed under the control of Aulus Plautius acting for the Emperor Claudius that they established control of Britain.
As the Romans spread over the country they constructed roads and one, the main route to the west which ran from London, through Staines, Swinley Forest then on to Silchester where it branched three ways - to Bitterne, Portchester then east to Chichester, to Dorchester then on to Exeter and to Cirencester and on to Gloucester. Today the road from London to Silchester is known as The Devil's Highway - a much later name, we don't know what the Romans called it though I have seen references to it as Portway. We know for certain that the road ran through the Forest but we cannot be sure of its exact path.
The second Roman site in the Forest is at Wickham Bushes where there is evidence of a small Roman and later Saxon town. Most of the evidence is in the form of Roman and Saxon coins, pottery and roof tiles. Its listing as a Scheduled Ancient Monument tells us that by 1975 partial excavations on the site had found remains of multi-roomed dwellings as well as the coins, pottery and tiles.
I believe that there is a further site adjacent to the town, of which more later.
A possible fourth site exists. Early (1800's) Ordinance Survey maps show the route of a Roman Road running from The Devil's Highway north to Caesar's Camp along the route of Lady's Mile Ride. This would be logical as a connection between the Roman Settlement at Wickham Bushes and the Atrebates settlement in Caesar's Camp. There is currently no archaeological evidence available to support this proposition.