It's a scary world out there right now. We still don't have a plan for Brexit. The Arctic isn't freezing like it ought to. Donald Trump is Donald Trump. So, let's take a moment off from our busy schedule of legitimate existential terror to talk about something pointless but comforting.

In 1943, London County Council commissioned Sir Patrick Abercrombie and John Henry Forshaw to produce the County of London Plan: a document explaining how the city would be rebuilt after the War to ensure it had adequate housing, transport and green space.

The Abercrombie Plan, as it became known, is one of the great urban planning documents, and one of the great “What ifs”, of British history. It proposed a system of “ringways”, motorway-grade orbital roads, and arterial roads connecting them; in between, urban areas would be separated by a network of parks. Some scraps of this plan came to pass (the Westway, the North Circular, the M25). Mostly, though, it never happened: as it turned out, people didn't want to demolish the city to build great big motorways through it.

Less famously, the Abercrombie plan also proposed a bunch of new railway tunnels. Which brings us to our map:

Click to expand.

It's not the easiest map to read, so here's what we're looking at:

Project A: The North Bank Loop, a new underground route taking trains from Battersea, to Victoria, Charing Cross and Cannon Street and on to Wapping and Deptford.

Project B: A second loop, taking trains that run into London Bridge underground into a new route connecting the stations on south and north banks of the Thames.

Project C: A deep level replacement for what is now Thameslink, carrying trains from Elephant and Castle through Blackfriars and onwards towards King’s Cross.

Project D: A new deep level version of the northern Circle line, freeing up the existing route to become a freight route (the “Inner Goods Ring”). Not shown on the map, there were also proposals for an Outer Goods Ring, somewhere or other – details on that are a bit sketchy..

Had the plan gone ahead, moss mainline trains from the south would be redirected to one of the new lines. All this, it was intended, would allow the city to tear up a bunch of overground railway linses and bridges, making it possible to redevelop the then-largely industrial South Bank.

These plans went through various iterations over the next few years. New lines appeared, too, including one variously known as “Route 8” or “Route C”: a fast, deep level tube line lining Finsbury Park and Brixton, which eventually appeared, in the late 1960s, as the Victoria line.

But mostly, it never happened. From the perspective of 2016, when the South Bank – railway viaducts and all – is doing rather well, this seems rather a good thing.

Some of these ideas still look pretty good, however. Imagine a sort of circular Crossrail, improving connections between the south London railway network and central London and freeing up space at the mainline terminals. We can dream, can't we?

Anyway, hope you enjoyed that. We now return you to the end of the world.

(Hat tip: David Turner.)

Jonn Elledge is the editor of CityMetric. He is on Twitter, far too much, as @jonnelledge.

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