Over 60s Railcard valid in London if not issues in London

WickedLady4

I've had my Oyster card for years (from when it only cost £3) and it's linked to my Senior Railcard, which gives me 34% discount on the Underground.
I also have 2 spares that get used by any visiting friends and family but they, understandably, cannot be linked. Very useful for friends from abroad who might get charged a percentage when using their contactless card, and not so much to worry about if it gets dropped or lost.