I have just ordered a railcard following the instructions here https://www.moneysavingexpert.com/deals/railcard/
where you pay £19.80 instead of £30 for one year. The catch is that in order to activate the railcard I need to book at least one train journey through the Trip.com website within 30 days of purchase before I can use my railcard.
I bought the railcard mostly to add its discount to my Oyster for travel on the London underground, and I won't be taking any train journey for quite some time. By I still need to buy a throwaway train ticket before I can have my railcard showing on my phone and added to my Oyster.
Hence my question: what is the cheapest single journey train fare in the UK (not London Underground)? Could be a 3 minute journey anywhere in the country