I've just renewed the Club's Cycling UK / CTC affiliation.
If you would like to join Cycling UK, or when you renew your membership if you are already a member, you can use the Club's reference number -
91014159 - to join at a discounted rate as an affiliated member.
This gives you pretty much everything the full membership gives you, apart from the magazine (if they are still doing that nowadays - not sure!). Most importantly it gives you third party insurance coverage, which is what you would need if you were deemed to have caused harm to someone or to property while riding a bike.
The Club advises all riders to have third party insurance coverage. If you are a member of British Cycling or LCC you will already have this cover. If not, this is probably the lowest-cost way to access it.
Frank