THE STANDARD KENYA Mzee Simon Njenga Kariuki, the 85-year-old man who Mukuru kwa Njenga slum in Nairobi was named after during his burial at Langata Cemetry. [James Wanzala, Standard] Many Nairobi residents have probably heard about Mukuru Kwa Njenga slum in Embakasi South Constituency. But perhaps few know the origins of the name and why a neighbouring slum was named Mukuru kwa Reuben. ‘Mukuru’ which means valley or quarry in Kikuyu, is one of the largest informal settlements in Kenya. It is divided into two by a railway line – carving out Mukuru Kwa Reuben to the west and Mukuru Kwa Njenga to the east.