When polar bears swam in the Thames

Description: To many people the Ice Age is a vague concept belonging to the remote past but geologically it was yesterday. Extraordinary evidence of the Ice Age continues to crop up on the British landscape in lion and hippopotamus fossils in Trafalgar Square, bear and hyena fragments in Devon, fossil remains of a polar bear from Kew. So when polar bears swam in the Thames, did Britain really look like present day Greenland?