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Junction of A5103 Princess Road with the A57(M) Mancunian Way is squareabout although the entry/exit points are at the corners rather than half way along the sides.
The best one I know is the M1 junction with the A50, A6 and A453. I saw it once from a plane taking off from East Midlands airport, and it really is square. The signage shows it as square, too.
avtur wrote:Junction of A5103 Princess Road with the A57(M) Mancunian Way is squareabout although the entry/exit points are at the corners rather than half way along the sides.
The M41 number was allocated to the western section of Ringway 1. The constructed section opened in 1970, and is now part of the A3220, having been downgraded in 2000. For the longest time it had none of its own junctions, but one was added for a shopping precinct shortly after it was de-specialised, along with the removal of its hard shoulders.
The road is unrelated to the A41(M) Tring Bypass, and was never allocated to any London–Birmingham route, despite an ongoing
avtur wrote:Junction of A5103 Princess Road with the A57(M) Mancunian Way is squareabout although the entry/exit points are at the corners rather than half way along the sides.
Outside the UK, three-level diamonds like this also have entry points at the corners of a square. But unlike the Mancunian Way example, the square is at right angles to the mainline.
Last edited by jackal on Mon Aug 08, 2016 13:45, edited 3 times in total.
avtur wrote:Junction of A5103 Princess Road with the A57(M) Mancunian Way is squareabout although the entry/exit points are at the corners rather than half way along the sides.
You could call that type a diamond-about.
There's one in Wythenshawe on Hollyhedge Road, or at least used to be.
Waterworks Roundabout on the north circular is a similar one, and the junction of the A10 and Dynant Link Road at Hoddesdon is a definate squareabout too.
The A563/B4114 is Leicestershire's second squareabout, and probably single-handedly responsible for keeping Peek in business.
More recently the Green Lane junction on the A453 in Clifton has been turned into a squareabout, works very well too.
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Truvelo wrote:They all tend to date from the same era.
Do you know what the design reason was for their popularity at the time? (excepting locations where a squareabout has been constructed to use existing roads, or to fit between obstructions)
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