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Patrick Harper wrote: ↑Thu Jan 11, 2024 20:38
The top-level flyovers at Swanley and Mardyke are classic examples.
By Swanley, do you mean Darenth?
Nope, he means Swanley (now M25 J3 / M20 J1).
When the junction was laid out in the mid 70s, the M25 bridge was placed over the M20 but not connected either side - not even any embankments - so was an isolated bridge to nowhere from 1977 when the M25 opened between J2 & J3 to 1986 when the M25 was finally extended to J5. As a side note the bridge was built wide enough for 2 lanes plus hard shoulder either way but when the M25 was finally built it was configured as 3 lanes but no hard shoulder.
Brenley Corner: congesting traffic since 1963; discussing roads since 2002
Patrick Harper wrote: ↑Thu Jan 11, 2024 20:38
The top-level flyovers at Swanley and Mardyke are classic examples.
By Swanley, do you mean Darenth?
Nope, he means Swanley (now M25 J3 / M20 J1).
When the junction was laid out in the mid 70s, the M25 bridge was placed over the M20 but not connected either side - not even any embankments - so was an isolated bridge to nowhere from 1977 when the M25 opened between J2 & J3 to 1986 when the M25 was finally extended to J5. As a side note the bridge was built wide enough for 2 lanes plus hard shoulder either way but when the M25 was finally built it was configured as 3 lanes but no hard shoulder.
Ah, okay. The high resolution 1973 USGS imagery that I downloaded to my hard disk last year shows nothing there aside from the pre-motorway D2 junction (which is still semi-intact), so I'm guessing work hadn't yet started on this junction at the time.
Are there any photos online that show the isolated bridge as it looked a handful of years later?
The M25 bridges over the M3 were in place when the M3 extension to Sunbury opened in Aug 74. I didn't know then what road was planned so they were a bit of a mystery. I called it the Bridge Showroom and would comically think to myself as I passed under them, 'I'll have one of that and 2 of those please'
RJDG14 wrote: ↑Fri Jan 12, 2024 14:40
Ah, okay. The high resolution 1973 USGS imagery that I downloaded to my hard disk last year shows nothing there aside from the pre-motorway D2 junction (which is still semi-intact), so I'm guessing work hadn't yet started on this junction at the time.
Are there any photos online that show the isolated bridge as it looked a handful of years later?
I lived in the area at the time but was only about 10 or 11 when the interchange initially opened. I'm guessing that work would have started in around 1974 or 1975 as the M25 to Dartford and the M20 to West Kingsdown opened in 1977 together with the initial layout of Swanley Interchange.
I have done some searching online but can't unearth any pictures. The bridge did become a minor 'celebrity' in the area at the time as it was so magnificently isolated at the highest level of a huge (for 1977) interchange roundabout for so long, so there must be pictures around but I cannot find them. I also understand that it was featured as an item of interest in a topical magazine TV programme with a song specially composed and performed from the bridge - again there is no easy trace online.
Brenley Corner: congesting traffic since 1963; discussing roads since 2002
MotorwayGuy wrote: ↑Fri Jan 12, 2024 15:07
There is of course the never used overbridge that would have taken the M23 mainline over the junction 7 sliproad.
RJDG14 wrote: ↑Fri Jan 12, 2024 14:40
Ah, okay. The high resolution 1973 USGS imagery that I downloaded to my hard disk last year shows nothing there aside from the pre-motorway D2 junction (which is still semi-intact), so I'm guessing work hadn't yet started on this junction at the time.
Are there any photos online that show the isolated bridge as it looked a handful of years later?
I lived in the area at the time but was only about 10 or 11 when the interchange initially opened. I'm guessing that work would have started in around 1974 or 1975 as the M25 to Dartford and the M20 to West Kingsdown opened in 1977 together with the initial layout of Swanley Interchange.
I have done some searching online but can't unearth any pictures. The bridge did become a minor 'celebrity' in the area at the time as it was so magnificently isolated at the highest level of a huge (for 1977) interchange roundabout for so long, so there must be pictures around but I cannot find them. I also understand that it was featured as an item of interest in a topical magazine TV programme with a song specially composed and performed from the bridge - again there is no easy trace online.
There is one USGS view that I discovered among their decent freely downloadable historic UK imagery (all of which I downloaded last year) yesterday of the M5/M50 junction in about 1968 when it was still a stub, though early groundworks appeared to be commencing for about a mile south (up to the bridge with the region's River Avon) in preparation for the southern extension. It was taken on an earlier system than the 1973 imagery (and I think was likely digitised earlier as well) and is not a particularly good quality image compared with the 1973 imagery as a result, but since it's in the public domain, I'll post it here when I re-find it.
Note though that I didn't originally intend this thread to mean junctions like it which were built as temporary termini with full privison for expansion, but rather ones more like the Swanley junction (assuming that it existed) and the junction at what is today J4 of the M6 as it was prior to the M6 being built. These were all isolated junctions with no other real purpose initially.
The 1967 One Inch maps section here shows what is today known as J23A of the M4 (the Magor junction) as a roundabout without any links, though with provision for the industrial road that was later built south of it:
Based on the pre-Second Severn Crossing M4, I would have thought it would have originally been J23. I'm guessing that it is labelled with an added A due to the additional M4 junction (the limited eastbound turnoff/westbound sliproad to/from the M48) that opened in the mid-late 1990s with the completion of the Second Severn Crossing, which increased the M4's junction count by one.
RJDG14 wrote: ↑Fri Jan 12, 2024 14:40
Ah, okay. The high resolution 1973 USGS imagery that I downloaded to my hard disk last year shows nothing there aside from the pre-motorway D2 junction (which is still semi-intact), so I'm guessing work hadn't yet started on this junction at the time.
Are there any photos online that show the isolated bridge as it looked a handful of years later?
I lived in the area at the time but was only about 10 or 11 when the interchange initially opened. I'm guessing that work would have started in around 1974 or 1975 as the M25 to Dartford and the M20 to West Kingsdown opened in 1977 together with the initial layout of Swanley Interchange.
I have done some searching online but can't unearth any pictures. The bridge did become a minor 'celebrity' in the area at the time as it was so magnificently isolated at the highest level of a huge (for 1977) interchange roundabout for so long, so there must be pictures around but I cannot find them. I also understand that it was featured as an item of interest in a topical magazine TV programme with a song specially composed and performed from the bridge - again there is no easy trace online.
It was Richard Stilgoe who sang a song on top of the bridge for the BBC show That's Life. He mentions it here, though I can't find a recording on YouTube.
My good friend Esther Rantzen then let me sing some songs on That’s Life, alternating with one of my idols, Jake Thackray. After hundreds of TV appearances (over 200 on Countdown alone) people only ever remember two things I did: one is a song called Statutory Right of Entry on Nationwide in 1974, which had seven of me in it, and the other is a song for That’s Life filmed on a bridge miles above the M20. The bridge had no road attached to either end then – it does now, it’s part of the M25 – but it looked very odd sitting in mid-air with me playing the piano on it. As is usual with television, people remember the image, not the words. Which is just as well – the song was called, to my shame, Bridge Over Troubled Mortar. The mortar was indeed troubled – while I was recording the song up top, the Kent C.I.D. were digging in the concrete for the remains of a hitman called Nino Ricci.
RJDG14 wrote: ↑Fri Jan 12, 2024 14:40
Ah, okay. The high resolution 1973 USGS imagery that I downloaded to my hard disk last year shows nothing there aside from the pre-motorway D2 junction (which is still semi-intact), so I'm guessing work hadn't yet started on this junction at the time.
Are there any photos online that show the isolated bridge as it looked a handful of years later?
I lived in the area at the time but was only about 10 or 11 when the interchange initially opened. I'm guessing that work would have started in around 1974 or 1975 as the M25 to Dartford and the M20 to West Kingsdown opened in 1977 together with the initial layout of Swanley Interchange.
I have done some searching online but can't unearth any pictures. The bridge did become a minor 'celebrity' in the area at the time as it was so magnificently isolated at the highest level of a huge (for 1977) interchange roundabout for so long, so there must be pictures around but I cannot find them. I also understand that it was featured as an item of interest in a topical magazine TV programme with a song specially composed and performed from the bridge - again there is no easy trace online.
There is one USGS view that I discovered among their decent freely downloadable historic UK imagery (all of which I downloaded last year) yesterday of the M5/M50 junction in about 1968 when it was still a stub, though early groundworks appeared to be commencing for about a mile south (up to the bridge with the region's River Avon) in preparation for the southern extension. It was taken on an earlier system than the 1973 imagery (and I think was likely digitised earlier as well) and is not a particularly good quality image compared with the 1973 imagery as a result, but since it's in the public domain, I'll post it here when I re-find it.
Note though that I didn't originally intend this thread to mean junctions like it which were built as temporary termini with full privison for expansion, but rather ones more like the Swanley junction (assuming that it existed) and the junction at what is today J4 of the M6 as it was prior to the M6 being built. These were all isolated junctions with no other real purpose initially.
The 1967 One Inch maps section here shows what is today known as J23A of the M4 (the Magor junction) as a roundabout without any links, though with provision for the industrial road that was later built south of it:
Based on the pre-Second Severn Crossing M4, I would have thought it would have originally been J23. I'm guessing that it is labelled with an added A due to the additional M4 junction (the limited eastbound turnoff/westbound sliproad to/from the M48) that opened in the mid-late 1990s with the completion of the Second Severn Crossing, which increased the M4's junction count by one.
Here's what the M5/M50 junction (at the time the Strensham Loop) looked like in 1968 according to the public domain USGS imagery (I've adjusted the EQ to bring down the clouds and improve the contrast from its very washed out state, and the sharpness to make the image a little clearer) when it was still serving as the temporary terminus of the southern end of the Midlands stretch of M5. At the time it looks like they were in the very early stages of building the M5 to the south.
The original low and wide arch bridge was built to carry the revised post-Staines Bypass route of the A30 in 1961. In 1981, a second similarly styled concrete bridge was added for the M25. The current road layout on the bridges is D2 (A30N) - D4 (M25N) - D5 (M25S) - D2 (A30S), with no hard shoulders on any of the carriageways.
The original low and wide arch bridge was built to carry the revised post-Staines Bypass route of the A30 in 1961. In 1981, a second similarly styled concrete bridge was added for the M25. The current road layout on the bridges is D2 (A30N) - D4 (M25N) - D5 (M25S) - D2 (A30S), with no hard shoulders on any of the carriageways.
It wasn't for a motorway, but this bridge over the River Nevis https://www.google.com/maps/@56.8245097 ... &entry=ttu was built in the 1970s for a local road to connect with the northern part of the A82 Fort William bypass ("Transport Centre to Kennels" scheme) which has never been built. It remained the responsibility of the trunk roads authority for decades despite only being open to pedestrians and cyclists.
The original low and wide arch bridge was built to carry the revised post-Staines Bypass route of the A30 in 1961. In 1981, a second similarly styled concrete bridge was added for the M25. The current road layout on the bridges is D2 (A30N) - D4 (M25N) - D5 (M25S) - D2 (A30S), with no hard shoulders on any of the carriageways.
The original low and wide arch bridge was built to carry the revised post-Staines Bypass route of the A30 in 1961. In 1981, a second similarly styled concrete bridge was added for the M25. The current road layout on the bridges is D2 (A30N) - D4 (M25N) - D5 (M25S) - D2 (A30S), with no hard shoulders on any of the carriageways.
RJDG14 wrote: ↑Sun Jan 14, 2024 11:28
My guess that one of the two M40 carriageways now covers the former alignment of the western half of the bypass.
No need to guess - go to SABRE Maps and select the 1972 One inch and use the map fader tool
Screenshot 2024-01-14 12.50.58.png
Yep, I did that.
While it unfortunately doesn't cover quite as far south as Warwick, the currently downloadable USGS imagery from 1973 that I have on my computer shows the A46 between Warwick and Coventry as being in the process of being dualled.
RJDG14 wrote: ↑Sun Jan 14, 2024 11:28
My guess that one of the two M40 carriageways now covers the former alignment of the western half of the bypass.
No need to guess - go to SABRE Maps and select the 1972 One inch and use the map fader tool
Screenshot 2024-01-14 12.50.58.png
Yep, I did that.
While it unfortunately doesn't cover quite as far south as Warwick, the currently downloadable USGS imagery from 1973 that I have on my computer shows the A46 between Warwick and Coventry as being in the process of being dualled.
But that imagery is irrelevant to the question at hand. If by "the western half of the Warwick Bypass you mean either:
a) the A46/A41 section that runs broadly north-south", then "No" the M40 does not cover any of this but crosses the roundabout broadly east-west as seen in the extract.
or
b) the western half of the A41 section between Bishop's Tachbrook and Longbridge, then the map extract covers most of this. I can confirm this as I was driving along the A41 daily for work during 1988-90
