BT Centre
Coordinates: 51°30′56″N 0°05′52″W / 51.5156°N 0.0978°W
The BT Centre is the global headquarters and registered office of BT Group, located in a 10-storey office building at 81 Newgate Street, London EC1A 7AJ, opposite St. Paul's tube station. It was completed in 1985. It should not be confused with the much more prominent BT Tower.
A plaque on the outside of the building marks this as the location from which Guglielmo Marconi made the first public transmission of wireless signals, in 1897 while it was the Telegraph Office building of the General Post Office complex.The Telegraph Office building was severely damaged by bombing in 1940 and demolished in 1967.
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