This promotional deal with Turkish Airlines is valid for bookings made in travel period berween 1st of February till 30th of June 2015. (except blackout period during Christmas holiday). This offer is valid for tickets booked till 31st of January 2015.
In some cases you may also combine each of the African destinations and book open-jaw flights. (no matter in which order, below are just a samples..). The easiest way to check your connection possibilities is through Skyscanner. This tool gives you quickly a rough idea which low-cost airlines are connecting your home town.
Booking samples
Booking is also available directly with Turkish Airlines - (i.e. Brussels - Nairobi for €402)
Brussels to Nairobi, Dar es Salaam or Entebbe from €381
Amsterdam to Nairobi, Dar es Salaam or Entebbe from €432
Italy to Nairobi, Dar es Salaam or Entebbe from €417
UK to Nairobi, Dar es Salaam or Entebbe from Ł293
Germany to Nairobi or Entebbe from €453
You may also book stop-over in Istanbul, below is booking sample when departing from Brussels:
Europe - Istanbul - Africa - Europe from €379 (+€22 booking fee)
Booking sample of cheap return flights to Africa (Kenya, Tanzania, Uganda) for €381 here. In this case you would fly to Nairobi in Kenya from Brussels on 9th of May. Your return flight from Africa back to Belgium would take place on 23rd of May 2015.