East Cross Route
The East Cross is the black sheep of the family: it's unusual because it is one of the few existing proposals that were absorbed into the GLC's comprehensive Ringway plan. It had been designed and partly built by the time the other three sides of Ringway 1 were unveiled, being a plan for general road improvement in East London that had been formulated by the former London County Council.
It is lower in standard than the other parts of Ringway 1 would have been, with an inferior alignment that makes use of existing roads (for this reason it was only ever a motorway for two short sections of its total length). It is also much narrower than the other proposals: documents relating to Ringway 1 and Ringway 2 (and even Ringway 3) inevitably refer to three- and four-lane motorways, but the East Cross Route is two or three cramped lanes wide and only has a hard shoulder where there's a bit of extra space. Arguably, there could have been an intention to substantially upgrade it as part of the Ringway plan, but no evidence has been found to suggest this.
Continues from North Cross Route
M11 and A12 (Hackney Wick Interchange)
A11 Bow & Stratford
Greenwich & Woolwich
Kidbrooke (local access)
A2(M) and A20(M) (Kidbrooke Interchange)
Continues to South Cross Route
The line of the East Cross Route is simple to trace as, impressively, the whole thing was built. Its northern terminus was to be at a large free-flowing interchange - part of a much larger junction complex along the M11 and A12 corridors - where it was to take over from the North Cross Route. This junction, Hackney Wick, was never completed but a journey along the East Cross Route makes it obvious to even the untrained observer that something bigger was planned. To the west the Eastway Extension was to plunge into the City to eventually end at Angel (compare and contrast with the Westway at the other side of London), and to the east the M11 and A12 ran parallel towards Leyton.
The East Cross heads south from here, and until 2000 it was under motorway restrictions on this section as the A102(M). It is now the A12. It has an impressive three-level interchange with the A11 at Bow Church (shortly after which the motorway ended) and some local connections before reaching the A13, which runs along the north bank of the Thames. The interchange that exists here, with absurdly constrained looped sliproads connecting the roads together, was intended as a temporary measure and was to be replaced as the Blackwall Tunnels were improved. Unfortunately there is nothing to suggest what the final configuration was to be. One new tunnel bore was added for southbound traffic when the East Cross Route was under construction, and a second new tunnel was planned to remove northbound traffic from the original Victorian tunnel.
Having crossed the Thames, the route continues south (the remaining section as a motorway again until the year 2000), with local connections for Greenwich and Woolwich, and the old A2 at the notorious Sun in the Sands junction.
The road's southern terminus was to be at Kidbrooke (shown left - click for a larger version). Here it would have passed the baton to the South Cross Route, and also met the incoming A2(M) from the east and A20(M) from the south-east. The four way junction here would have looked quite odd, handing priority to straight-through flows so that the East Cross flowed on to the A20(M) and the South Cross became A2(M). Traffic wishing to stay on Ringway 1 would have had to exit and use tightly curving sliproads to make the connection.
At the time of its construction, the Blackwall Tunnel was given a second bore to bring it up to dual two-lane standard. However, the original tunnel was built in the nineteenth century and has a poor alignment and a low roof. It was originally envisaged that a third bore would be opened at a later date to allow the motorway to pass through modern tunnels, but the third bore never happened. It does still get talked about: proposals (and a dashed line marking the route) appear in A-Z street maps as late as the 1980s and it is thought, though not conclusively known, that the plan was never formally scrapped.
At the southern end of the road, the small junction south of Sun in the Sands was the original terminus, dumping all the motorway traffic onto the built-up Rochester Way towards Eltham. When the Ringway plans were dropped, the traffic situation in Eltham was so bad that the former A2(M) plan was resurrected and the ensuing construction works were the largest and most complex new road in London in the 1980s. Today the East Cross Route does reach Kidbrooke, but while the junction is approached by two grade-separated roads designed in the Ringway era, they are connected by a flat signalised interchange.
The numbering for this section of road causes some confusion. The section north of the Thames held the number A106 for a short while, before becoming A102 and A102(M). This seems a very unlikely number for one side of Ringway 1, and it seems most likely that it was intended to be a temporary designation, but there is no evidence to suggest what its final number was supposed to be. The only other clue is on the other section that was built - a fragment of the West Cross Route - which was numbered M41. This number seems equally unlikely.