Officially opening tomorrow , London's tallest building : the 620 ft Post Office Tower with , at the very top , its sensational Panorama of London revolving restaurant . But the restaurant won't be ready for business until the Spring and opening night , date of which hasn't yet been fixed , is fully booked . Hundreds of early applications for tables in the 120 seater eating out place have been received . The 瞿2 500 000 Post Office Tower's supremacy of the London skyline is unlikely to be rivalled . Higher buildings are banned because they could interfere with radio waves from the tower's aerials , which eventually will make possible 10 000 simultaneous television conversations and transmission of up to forty television networks . There are 29 storeys . 7 October 1965