Africa's 'vertical slum': Images show the tallest apartment block on the continent - a 55-storey 'dystopian' tower in Johannesburg

• The Ponte City tower in Johannesburg, South Africa is 567 ft tall and has 55 storeys of flats
• The tower was built in 1975 and fell into disrepair over subsequent decades, and became 'vertical slum'
• However, it has since been renovated and residents have returned to the unique cylinder blocks
• The building has been used as a location for sci-fi thrillers District 9 and Resident Evil: The Final Chapter