11 Diagonal Street

11 Diagonal Street is a 20-story commercial building in Johannesburg's main business district, built with a distinctive glass facade that features angular geometric lines. The structure houses office spaces and functions as a landmark within the cityscape due to its striking modern design.

German architect Helmut Jahn designed this building, with construction starting in 1983 and opening completed in 1984. The project emerged during a period of significant commercial growth in Johannesburg's downtown area.

The building's angular glass exterior draws inspiration from South Africa's diamond mining heritage, incorporating this element into modern architectural design.

Multiple elevators service the building's floors and allow easy movement throughout the office spaces. Visitors should note this is a working commercial building, so access to common areas may be restricted during business hours.

The glass exterior reflects light differently throughout the day, creating changing visual effects as sunlight moves across the structure. This quality makes the building appear distinct from various vantage points around the city.

Location: Johannesburg

Inception: 1983

Architects: Helmut Jahn

Official opening: 1984

Floors above the ground: 20

Elevators: 6

GPS coordinates: -26.20417,28.03583

Latest update: December 10, 2025 16:29