You could do worse than spend six quid on Mike Horne's excellent book for Capital Transport, "The Victoria Line: An Illustrated History", as he gives the answer in quite some detail. Anyhow, to cut a long story short, several options were looked at for a NE-S tube railway in the years immediately after the end of WWII, most of which went from Walthamstow to KX, Oxford Circus, Victoria, Brixton and on to East Croydon (with one option coming in from Hitchin to Finsbury Park, then as above but southwards from East Croydon to Coulsdon North and Sanderstead). The plans as finally approved (in 1962!) were to take the line from Wood Street to Victoria but the business case for building the line from Wood Street to Hoe Street (now Walthamstow Central) were marginal and so this section was dropped.
The idea of a line generally the same as the Vic was first put forward by LT in 1937. Between then and actual completion, there were dozens of changes of plan.
The route orginally authorised by the 1961 Act had the Walthamstow terminus in the open at Wood Street, with cross-platform interchange with BR's Chingford services. The electrification of the Chingford line would have made this project very complex, so the line was cut back to Hoe Street.
Another late change was the station at Warren Street.
For full details, read MAC Horne's "The Victoria Line": it's only a few quid.
Thought the last change was the addition of Pimlico, the only non-interchange sation.
There was also some controversy about the fact that the tunnels didn't take the direct route between Green Park and Victoria, thus avoiding Buck Palace. Claimed to be due to 'geological conditons'.
Security reasons more like, imagine another 7/7-like incident (apologies to those who may be offended by the example) in the tunnel under the Palace, while the Queen's inside even! No, much more secure to divert the tunnels IMO, even if it does take longer and costs more.
I remember hearing that the original route wuld have taken the vic south of brixton and through my area i.e norbury on its way to croydon.
There was discssion around 1958-60 about whether the Bakerloo should be extended to Camberwell and/or the Vic to Fulham, Wimbledon, or Croydon. In the end it was decided that none of these would offer value for money.
One of the first planned route for the Victoria Line was a Green Park, Bond Street, Great Portland Street, Camden Town line with two branches in the north, one to Walthamstow and the other one to Enfield Town. In the south he line would have reached Croydon and Coulsdon. See more here: www.davros.org/rail/culg/
Let's hope that one day the line will be extended further south.
My grandad who is dead now, was the chief engineer on the line when it was being built. I am sure if my step grandma wasn't the hag she is i would be able to find some plans maybe on the building of the line. I didn't see him much so i didn't ask him about it, so really i am no help.
But still it is one of the most used lines on the system. (i think?) My grandad was on the queens train when it opened since he was incharge but wasn't in the cab the senior partner was who didn't even work on it lol!
Considering how busy the Victoria Line is, it can certainly be said that the correct route was chosen, and the line was very good value for money!
and to think that when it first opened they were worried that the line might not attract sufficient traffic!
It is quite amazing that there was so much umming and eerring before the line was finally built. I would hate to think of how busy the SSLs must have been at Victoria before the Victoria Line was built.
The Victoria Line was generally quite well designed for the number of passengers that it was expected to carry e.g ATO, shallow curves and high speeds, high reversing capacity, and spacious stations (compared to older stations in London).
Unfortunately it is now much busier than originally expected, and the line capacity (restricted by signalling and dwell times), reversing capacity, and station passageways are now at their capacity limits. The VLU isn't going to realistically improve capacity more than 10-15%, in which time passenger numbers could increase by a higher percentage anyway.
The JLE extension learnt from the Victoria Line, by super-sizing stations to allow for future capacity increases, although improved safety regulations were also a bigfactor in the JLE station design. However these super-sized stations came at a very very big cost!
I will answer the question about Victoria station if I may. Before the Vic line came it was LESS busy than it is now. Oh yes there were lot's of folk coming down from the main line upstairs but never overcrowded platforms. Most trains were already packed coming from the west anyway and thiose that piled in at Victoria were only short distance travellers. To St James's and Westminster. It was EMBANKMENT [ then Charing X] where the crush loads used to be even with a 90 second service.
i've seen a 50s plan that uses the current Victoria north of Victoria, and the Chelney route to Wimbledon south of it. There were late 40s plans for it to not serve Walthamstow, but to go via Northumberland Park up the Lea Valley. other plans include Chelney alignment (TCR, PCirc) from KX to Vic with Croydon via Brixton and Walthamstow as the ends.