Can you change old French Francs in London?
You can still convert French Francs, Italian Lira and other
pre-Euro currencies notes and coins back into pounds Sterling.
Thomas Exchange UK can usually convert most old pre-Euro
currencies back into Sterling and they also convert some of the
coins as well , a guy called Paul is their obsolete currency
expert.
The best bet is to bring the notes to their West End branch in
London (near Oxford Circus Station) and they will then convert the
notes/coins into Sterling cash. Or, if you are based outside
London, you can post the notes/coins to them and they can pay you
by check (but ring in advance before you post).