Good evening, and thank you for your patience. I've now consulted several people: Firstly the people who live in the house, who believes it is an unnamed offshoot of Station Road, and their letters are addressed as such. Secondly I consulted the former chair of the historical society, councillor for 50+ years, and encyclopedia on Llanfairfechan history and road and house names. He did not believe the road is named either.

That means that: 1) the only source for this seems to be findmystreet or NSG/GeoPlace (or a derivative of those) which I not believe is a permissive source (and I suspect they added a descriptive name rather than an actual name). 2) That the openly available (and permissible) data from Ordnance Survey OpenData does not have a name for the road. 3) The people who live there does not believe road has a name. And finally 4) The encyclopedia on Llan history believes it to be a mistake.

I think it is fair to say that the name given by findmystreet/GeoPlace/NSG is likely descriptive and should not be used as a street name, and has no local precedent, especially the English transliteration.

As such, I think it would be fair for the name to be removed unless an actual permissive source can be obtained.

I won't make any changes today as I want to give you time to respond whether you think that is a fair assessment.

I apologise for the long comment.

Update: I can confirm that the name is not in OS OpenData Roads or Names. The road itself is in the TOID reference tables that link OS TOID with USRNs, but not it is not linked to any name.

According to NSG/GeoPlace (which I am not sure is acceptable to use due to copyright), the name is Afon Dale in both languages: https://www.findmystreet.co.uk/map?usrn=46606500

According to the OS Open Data (which is under the Open Government Licence, hence permissible), the road has a USRN, but it doesn't seem to have a name.

I think the correct English name would be the same as the Welsh, if it has a name at all that is possible to get from permissible sources.

Thank you for the clarification, I just wanted to be sure. Having searched around for a while, it seems to me that as long as it came from OS Open data (osm.wiki/Ordnance_Survey_OpenData) it is fine, while if it came from Geoplace (i.e. NSG) then it probably isn't since their licence is more strict.

This comment applies to the road naming over at the end of Pendalar as well, but is the data from NSG copyright compatible with OSM?

Sorry I feel obligated to comment here as well. According to the USRN map this is part of Pendalar, but there is no sign anywhere, and the addresses are not on Pendalar or Penmaenmawr Road. Are you sure that this is right? The only source I'm able to find for it is Google Maps, but I don't trust that.

What is your source for this? I'm just sceptical that an unmarked driveway with one house on it is a named road with the same name just transliterated into Welsh?

Do you have a source that shows that this road is part of Park Crescent rather than being an unnamed alleyway? None of the houses on the road have an address on Park Crescent and there is no sign on either end.

No problem!