This is my wiki site about London which will also link to the current pub history site
The best way to find the original London wall in Roman London appears to be through sewer excavations, and similar excavations. These pages are based on a "Royal Commission On Historical Monuments 1834" - actually it is 1928; which is in the public domain. A section (page 83) onwards lists a number of archaeological excavations of the original London wall, and some detail and illustrations.
A mapping of the area is always good, modern day compared to pre-1900 maps from the NLS site
(1). Wardrobe Tower, Tower of London.
(2) . Bowyer Tower, Tower of London.
(3) . Trinity Place, South
(4) . Trinity Place, North.
(5) . Cooper's Row.
(6) . Southend (formerly Blackwall) Railway, South.
(7) . Southend (formerly Blackwall) Railway, North.
(8) . America Square.
(9) . Roman Wall House.
(10) . The Cass School.
(11) . Jewry Street, North end.
(12) . Duke Street.
(13) . Bevis Marks, East end.
(14) . Bevis Marks, East of Goring Street.
(15) . Bevis Marks, West of Goring Street.
(16) . Camomile Street, East.
(17) . Camomile Street, middle.
(18) . London Wall, East of All Hallows Church.
(19) . London Wall, All Hallows Church.
(20) . London Wall, All Hallows Churchyard.
(21) . London Wall, West, corner of Blomfield street.
(22) . London Wall, opposite Carpenters' Hall.
(23) . London Wall, between Throgmorton Avenue and Moor gate Street.
(24) . London Wall, Copthall Avenue.
(25) . London Wall, immediately West of Moorgate Street.
(26) . London Wall, East of Coleman Street.
(27) . Aldermanbury Postern, North East side.
(28) . St. Alphage Churchyard.
(29) . East of Aldersgate Street.
(30) . West of Aldersgate.
(31) . St. Botolph, Aldersgate churchyard, South side.
(32 - 35) . Christ’s Hospital site (A to D).
(36) . Immediately North of Newgate
(37) . Newgate Prison site.
(38) . Warwick Square, West side.
(39) . Nos. 7-10, Old Bailey.
(40) . South of Ludgate
(41) . Upper Thames Street (A).
(42) . Upper Thames street (B).
(43) . Upper Thames Street (C).
(44) . Upper Thames Street (D).
(45) . Upper Thames Street (E).
(46) . Upper Thames Street (F).
(47) . Lower Thames Street (A).
(48) . Lower Thames Street (B)
Low