tubechallenge.com

I have been rightfully made to migrate this intriguing proposition to Zone W

As follows:

Around what axis would it be cheapest to rotate the whole London Underground network by 90 degrees in any direction; this would require the demolition, transportation, and reconstruction of all rails, stations, and LUL infrastructure? This would have to be a precise and exact tranformation; equating for the altitude of stations for instance. Any current London structures in the way would have to be demolished for the sake of the underground. How expensive would it be?

Sorry, Oggm, my reply in the other thread wasn't intended as a criticism, but I felt your question was fascinating enough that it deserved a thread to itself

Am I right in thinking that the axis does not have to pass through or close to London?

No worries, I was initially presuming the axis would be in London, but I guess my rules have not been strenuous enough; therefore, yes, the axis can be anywhere space in 3D space (i.e., the world and space and everything else). Providing it is straight and continuous.

Blimey, what a surreal question!

Here goes with some thoughts rather than a definitive answer. It feels like there are two questions: where is the centre for rotation and which way does it rotate. That then suggests something based around average property prices coupled with engineering complexity. Restricting it to 90 degree rotations feels quite constricting too but avoids silly calculations.

One approach would be to rule out expensive counties such as Buckinghamshire, Berkshire and Oxfordshire, although this has the disadvantage of affecting Northamptonshire and cheaper parts of Hertfordshire. Hampshire, Surrey and West Sussex feel too expensive too.

So, a rotation that involves south Essex and north Kent feels like it has a financial advantage as well as a geographical advantage of being closer to the sea level of the Thames estuary.

The failure of the UndergrounD to penetrate SE London suggests that north of the river is a better bet. The danger of going as far north as Epping suggests the risk of encompassing expensive places in Essex and Suffolk for those Down From London.

So, for starters, I'll suggest a basic 90 degree clockwise rotation around Upminster.

Thoughts?

If rotation multiples of 90 degrees were allowed, I might go for 180 degrees from, say, Fairlop

Bearing in mind much of the Underground is close to sea level, a rotation that lands in the flats of East Anglia could be a good candidate.

With the optimum rotation, tunnelling could be minimal, and the lines could run in cuttings and on embankments. This could reduce costs. And it’s very sparsely populated, so not too much demolition either.

Perhaps you could match the high points of the topography to keep things even cheaper. So for example, a fulcrum somewhere near Bedford with a 90 degree rotation anticlockwise should transform the high point of High Barnet onto Ely…

Maybe. Maybe not. Who knows?

My first (out of the box) thought was, what if you rotated the Tube vertically? If you stood it on end, at say Upminster, it would have a very small footprint, and so minimal land cost, but the construction costs of building up to Chesham and Amersham many miles in the air would be astronomical!

However a better thought was "what if you rotate about the Earth's axis"? i.e. North Pole to South Pole?
This would put Piccadilly Circus at 51°30′36″N 90°8′4″W, in the wilds of Ontario, Canada, where I would imagine the land is pretty cheap and the biggets expense would be chopping down trees.....

RJSRdg wrote: ↑08 May 2025, 00:25 My first (out of the box) thought was, what if you rotated the Tube vertically? If you stood it on end, at say Upminster, it would have a very small footprint, and so minimal land cost, but the construction costs of building up to Chesham and Amersham many miles in the air would be astronomical!

Perhaps a vertical rotation would work; however, The Underground presumably spans more than 30km; resultantly, it would not reach from the bottom of the crust to the top of the atmosphere (10+20km). I'm pretty sure it is physically and legally impossible to build free standing structures in space.

This induces annother question; perhaps with an actual answer: What is the shortest profile of the London Underground when viewed parallel to the surface?

Oggm wrote: ↑11 May 2025, 08:10

RJSRdg wrote: ↑08 May 2025, 00:25 My first (out of the box) thought was, what if you rotated the Tube vertically? If you stood it on end, at say Upminster, it would have a very small footprint, and so minimal land cost, but the construction costs of building up to Chesham and Amersham many miles in the air would be astronomical!

Perhaps a vertical rotation would work; however, The Underground presumably spans more than 30km;

Almost exactly twice that in fact, being 60km from the buffer stops at Upminster Depot due west to a point due south of Chesham.