The original Mailbox in Birmingham was designed by R. H. Ousman of the Ministry of Public Building and Works, who collaborated with project architect H. A. E. Giddings and Hubbard Ford & Partners. The building was completed in 1970 and was the largest mechanised letters and parcels sorting office in the country with a floor area of 20 acres (81,000 m2) and the largest building in Birmingham. A tunnel connected the Mailbox to New Street station allowing the direct transfer of