In 1976 the GPO (later British Telecom) opened the world's largest international exchange on the site, due to the hold ups in the construction of their new Mondial House, with the "De Havilland" Plessey TXK2 and "Mollison" Ericsson TXK5.
In 1976, British Telecom (formerly GPO) launched a massive international switching center on the site, caused by construction hold-ups for their new Mondial House, employing the "De Havilland" Plessey TXK2 and "Mollison" Ericsson TXK5.