11_diagonal_street | buildingstartdate | 1978 <sep> 11 diagonal street is an office tower in johannesburg, south africa it was built in 1983 to a height of 80 metres it is designed to look like a diamond as it reflects different views of the central business district from each angle of the buildingthe building's architect was helmut jahn 
the 11 diagonal street originated in 1978.no information