It is possible today to "take a walk" round where the wall was, locating its position via its famous gates which names are still in existence today.
Starting in the west at present day Blackfriars Bridge walk north only about 200 yards to "Ludgate" (now Ludgate circus).
The old Roman city must not have been worth inhabiting for rural peoples?
For those who know London this area would obviously have made a good port with immediate access to high dry ground.
The original Roman settlement stretched from The Walbrook river (Cannon Street Station) in the west to the Tower of London (which did not exist) in the east.
The second river is the Fleet just over a quarter of a mile west of the Walbrook which is a much larger river and flows north south under present day Ludgate circus and Farringdon street.
International trade through this port would have been mainly sheep's wool and woollen clothes for which Britain was famous.
That is commencing in London, east of the river Lea and Lea Marshes and running north south through present day Wathamstow. This was a relatively stable division as the Saxon rulers in London persuaded the Danish Vikings to stay in their allocated territory in return for a regular monthly income of silver pennies minted in London.
(Note the present day embankment did not exist.) The only building of note in the old Roman area which was used by the Saxons was the site of St Paul's for a church of that name.
There was also a Saxon Palace (position not known).
They also imported bronze ornaments, pottery, glass and millstones.
London would have had all the trappings of Rome at that time.