On 2012-06-08 12:38:44 +0000, Neil Williams said:

wrote:

Why do some london bus routes have a letter in them? Its not like numbers are
in short supply. Do the letters signify something special?

Yes, they refer to the areas in which very local buses operate to avoid the
need to use very long numbers. So W is Walthamstow, U is Uxbridge etc.
RV1 is a special case, meaning RiVerside, though I have no idea if there
was ever planned to be an RV2 or just that it's convention for bus numbers
to actually contain a number of some sort.

Neil

This all goes back to the Reshaping London's Buses scheme that started
in 1968. The changes were made area by area, and one of the first to go
was Wood Green. Flat-fare single-deck standee routes W1 - W6 were
created there, with W standing for Wood Green, followed not long after
by W7, a direct replacement for the 212. Walthamstow soon got the
treatment and acquired flat-fare W21, Ealing got the E1, E2 and E3, and
Morden the M1 (ex 151).

Some later routes just joined in existing nearby numbering schemes, so
Enfield got the W8 when the 128 went flat-fare, and the W9 when it got
the minibus.

Years earlier letters were much more common on London bus routes, but
as suffixes. This is down the Met. Police and a commisioner called
Bassom, who insisted that every variant of a route had to have a
separate number. This lead to, for instance, the 406F running between
kingston and Tattenham Corner until not too long ago.

Even when Bassom numbering was no longer mandatory, LT still used
letter suffixes for route variants. For instance, there were routes 2,
2A and 2B running between various combinations of North Finchley (and
probably much further north once), Victoria, Norwood and Crystal Palace
via more than one routing. And the 4A (Farringdon Street - Finsbury
Park) was not the only example of a suffixed route that had no
unadorned version.

Even the Green Line coaches used suffixes: 715 was Guildford - Hertford
via Wood Green; 715a was Oxford Circus - Hertford via Tottenham. There
were also routes 716 and 716A.