Any town that produced an Olympic gold medal winner can have a gold painted post box, courtesy of GPO, or whatever they call themselves nowadays. But only Hull can have a golden telephone box. This is because our kiosks don't belong to BT, or whatever it calls itself nowadays. They used to belong to the people of Hull until Thatcher forced us to sell it off to the privateers. Now it belongs to God knows who. Last time I heard some French outfit owned it, not, one hopes, criminals such as ATOS (who cull Britain's weak and helpless), or Veolia (the poisoners of Palestinian land).
The story of the Hull area telephone system is an interesting one. The city was a pioneer in the field, and continued in the forefront ("the cutting edge") of telecommunications until fairly recently. Now it's just another moneygrubbing outfit with shareholders to pacify and customers to fob off. Still independent of the national network however.

There may be something on the Hull Telephone Service/Kingston Communications on wikipedia.