Pointless speed limit sections

[brad465]

I was recently reminded that Ramsgate-Dumpton Park (over the viaduct) used to be 90mph, which had to be the most pointless section of 90mph possible, because the speed is 30mph through Dumpton Park, while Ramsgate also has a low speed and everything calls there as well. More recently it was lowered to 50mph, but even this probably isn't reached.

What other sections of linespeed exist where it is physically impossible for any train using that section to reach the top speed, and why do such limits exist in the first place?

 

[PGAT]

Heading North from West Croydon the line is 60mph briefly before dropping sharply to 20mph right before Gloucester Road Jn, and the approach to the station is only 45mph.

 

[zwk500]

and why do such limits exist in the first place?

I expect that in most cases it will be because there was originally a 'ruling linespeed' and individual Permanent Speed Restrictions were only noted in specific places. At some point, it was decided that the distinction between the 'ruling' speed and PSRs was done away with, and anywhere not with a PSR was defined at the original Ruling Linespeed.

You can still see traces of this in the Southern Region sectional appendix where the front page of most (all?) Lines of Routes has a list of the sections and their ruling linespeed.

For instance, Victoria to Selhurst is given as a ruling speed of 60mph, despite PSRs of 25mph at Victoria, 40mph Victoria to Grosvenor Bridge, and 45mph Grosvenor Bridge to Pouparts Jn (for passenger traffic)
Now, you may ask why NR hasn't gone through and corrected anomlies like this, and the answer to that is disproportionate cost for the need/benefit. It takes a lot of work to demonstrate the case for a speed change on the railway, and all potentially impacted operators must be consulted. So speeds only tend to be changed if there is a commercial reason to increase them, or a safety/engineering reason to decrease them. Paperwork being 'neater' does not (sadly) meet the threshold for spending money.


== Doublepost prevention - post automatically merged: 15 Jul 2026 ==

I was recently reminded that Ramsgate-Dumpton Park (over the viaduct) used to be 90mph, which had to be the most pointless section of 90mph possible, because the speed is 30mph through Dumpton Park, while Ramsgate also has a low speed and everything calls there as well.

The sectional appendix shows linespeed 90mph max to Ramsgate:

In the same vein, there's a slightly less than 76 chain (1.5km) section of 90mph on the Down Lewes just after Keymer Jn, sandwiched between the 30mph coming off the junction curve and a 75mph section:

The 'ruling' speed here is almost certainly why the line goes to 90 then drops to 75mph rather than just rising to 75mph. It takes 8 seconds longer to cover 1 mile at 75mph rather than 90mph. Allow for acceleration and braking and the time saving is nil.