....the reason it's several, is London used to have several cablecos each with its own headend.
You may be thinking of the super headends:
Ex Telewest in Knowsley
Ex Ntl in Langley
Ex CwC in Bromley
Anyway, this will all change/is changing with all the new cisco gear being put in as part of the next gen network. Me thinks there will be lots of consolidation going on, might even end up with just one network in the end.
