Wikipedia:Articles for deletion/Crawfordsburn Viaduct
https://apps.communities-ni.gov.uk/Buildings/buildview.aspx?id=6360&js=false Listed building. So obviously the experts don't regard it as an "unremarkable bit of civil engineering". Therefore clearly meets  and does have a very good source. And the railway it serves does have an article, albeit a short one that doesn't mention this structure: Belfast–Bangor line
— User:Necrothesp, 13:35, 21 February 2018 (UTC)
Stance: keep
Cited policy: WP:GEOFEAT (Wikipedia:Notability)