The border you have removed was not a current administrative border but between the "traditional" counties of Essex and Hertfordshire, which has changed in the course of time, as you can see here: https://maps.nls.uk/geo/explore/side-by-side/#zoom=15.0&lat=51.86329&lon=0.17397&layers=10&right=osm
Removing a segment of the boundary breaks things for others, please revert this change!
Regards, Colin

The administrative boundary with its seaward extension is CORRECT, however odd it may seem. I will revert these changes. If anyone wants to discuss this, please get in touch BEFORE screwing up the data.

Hi John. The MLW thing is default, and technically it's MLWS in Scotland. But as you correctly point out there are exceptions, created in law and known as Seaward Extensions. Big ones that come to mind include Brighton Marina and the Bristol Channel. I'll take a look at Rosyth and Boness - I'm not so familiar with the Scottish coastline as I am with the south coast!

Hi, thanks for responding.
We need to establish what is meant by "Redcar" here. Is it the conurbation (built-up area), post town, some council area, an electoral area (parliamentary constituency, ward, county electoral division etc) or what? They are all distinct entities, and can all have their own boundaries in OSM, but need to be tagged in the appropriate way. Boundary=urban is (AFAIK) scarcely used in the UK.
To be an admin boundary, it needs to represent the area for some kind of official body with democratic status, possibly in this case a Town Council (civil parish) but there isn't one here.
The line in question is not one of mine, and I have no idea what it intends to represent; I removed its "boundary=administrative" because that is definitely not correct. I work from legally established data, such as Ordnance Survey Boundary-Line.

Please explain a) why Redcar (town) should have an admin boundary in OSM and b) why this line is a correct representation of it

Hi Matty,
There wasn't a level 10 boundary for Redcar because there is no Redcar town/parish council. What source did you use to establish that this is the boundary of "Redcar"?
Also, it is "traditional" to re-use boundary segments where that makes semantic sense. In this case, if "Redcar Town Council" should come into existence, its boundary would be shared with the adjacent admin areas, so there is no overlap possible.

Hi Paul,

Thanks for your observation!
The deletion was correct. Llangwm was a separate community until 2022, when it was merged with Llantrisant Fawr. I meant to delete it when I made that edit, but I must have missed it and someone else got there first!
By the way, there is still another community called Llangwm, in Pembrokeshire: relation/11180866
Regards, Colin

Just curious... Where did you find the postcode boundaries (not the centroids)?

Hi Ryan, indeed, you selected the wrong "way". I think your customer meant that the bridge over the railway line is closed to all (motor) vehicles (and not the whole length of Broadmead Road). This appears to be already correctly mapped in OSM; no moto vehicles, taxis included, should be routed across the bridge itself. For future reference, marking a road as "motor_vehicle=no" would achieve what you wanted. Just "taxi=no" wouldn't stop a bus or a car for example.

Hi Ryan... In this changeset you have added "taxi=no" to a couple of electoral ward boundaries. I suspect you meant to add them to the roads which they follow.
Did you really mean that these roads are forbidden for (all) taxis? I'm checking because that sounds rather implausible, and I have no idea how that would be made obvious in terms of road signs.

How does one interpret designation=public_footpath in combination with access=no? Specifically here: way/399112196#map=16/51.67607/-2.19830
Strangely this way is both a footpath and an admin boundary. As both can be considered "primary function" it would be better to separate them into their own ways, even if they are perfectly colinear.

Please revert these changes. railway=preserved is problematic and has been superseded by railway:preserved=yes. Please refer to railway=preserved?uselang=en-GB

That the authority has an elected Mayor. Not all Combined Authorities do.

Hi,
Please change this back. In general we don't use admin_level=9 in the UK. Town councils are administratively equivalent to civil parishes, and both fit at admin_level=10.

Sounds a bit redundant, tbh. A bit like "this page intentionally left blank (apart from this text, obviously)"

Hi Paul,
Formally, unparished areas don't have a name. They often cover wide areas containing many settlements, making it difficult to imagine a sensible name for the whole area. Sometimes they are created by the abolition of a civil parish, so I guess the name of that could be carried over. But in any case the boundaries of a settlement in the UK are notoriously vague - pick a point between two villages and ask a sample of people "where am I?" and you are unlikely to get a clear consensus unless it's "somewhere between A and B."
Regards, Colin

i agree with @DorneyLake123, I will revert to admin_level=9

This is incorrect. I will revert this change.

i think you meant to connect the new N-S cycle track to the existing E-W path, not to an admin boundary.

the problem was the role, not the membership. please take care to fix the problem and not just cover up the symptom.