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London's landmark through the years - in picturesThe BT Tower, one of London's most famous landmarks, was opened by the then Prime Minister Harold Wilson 40 years ago on 8 October 1965.
All photos: VisualMedia
Originally known as the Post Office Tower, it was the UK's highest building at the time, standing 189 metres tall including a 12 metre London Weather Centre radar mast.
The tower was designed to meet the increased demands of broadcasting by allowing the use of microwaves instead of landlines for transmitting television signals.