Prospect London Central Retired Members Group
Prospect's Retired Members Group is actively involved in the National Pensioners Convention, and encourages retired members to take an active interest.
Retired members who used to be Civil Servants might like to become involved in the Civil Service Pensioners' Alliance.
Retired members who used to be Civil Servants might also like to join the Civil Service Retirement Fellowship.
Try the University of the Third Age for stimulating the mind in retirement.
Age UK is the new force combining Age Concern and Help The Aged. The website has a "Your Location" facility to enable you to see what Age UK does in your area.
The London Society has a programme of over 20 events a year, mainly visits to places, buildings & institutions of interest. It also regularly publishes material about the capitol.