Most of the small-ish towns to the north/west of London seem to have just one or two 'proper' music venues - I'm talking about Slough & Maidenhead, Amersham & Chesham, Watford & Berkhamsted, Hatfield & Welwyn GC. Some do slightly better than that (High Wycombe springs to mind) but the absolute stand-out is St. Albans.
That town seems to have as many music venues as the rest of Hertforshire put together, but every band for 50 miles wants to play there so the competition is unreal. On principle, I never waste my time seeking gigs in St. Albans. 🙄