OK, to keep Lethal happy, here is a logical explanation for how this region of South London came to have such a peculiar name.

In the middle part of the last millennium the European Royal Families often inter-married -- after all, who was a princess fit to marry if not a prince. The Spanish Princess Royal is traditionally named the Infanta da Castille. Reputedly one of these Spanish Princesses, on her way to London to meet her potential future husband, rested overnight at an inn in this area and the local inhabitants were so impressed with her grace and beauty that they named the inn in her honour. Over time this became corrupted to Elephant and Castle and gradually as London expanded outwards, this name became associated with the entire area.

As to the lack of either elephants or castles here, well that's hardly surprising considering it's now a quite run-down area of inner city London. To most people these days Elephant & Castle is either a tube station or a very large roundabout surrounding an ugly shopping centre.