[turretslug]

I can't help thinking that leaving the PO/BT tower off the OS maps would have been a rather good way of drawing the attention of the spooks from the other side to it! As said, it seems rather more likely that there was a period between its construction and the next OS survey. Otherwise, this sounds like a classic case of how a "three'n'fourpence" story evolves and becomes urban truth.

Yes, any reasonable structure that pokes its head above other things in the vicinity has considerable appeal (and presumably consequent rental value) for the ever-increasing web of comms, even if obsolescent for its original purpose- at least the crazies will find it difficult to set light to concrete water towers.