All the recent Africa eppys were filmed in South Africa.
Lets face facts, you got yours wrong!!!!!!!!!! off to Africa ~~~~~VERY Proud member of the Troll Free Zone~~~~~ ******** The ship is canon baby!!!!!!!!!!!!!!!!!!!!!!!********
I remember reading that a lot of the time in season 9 n 10 they used green canvas background for the chicago scenes because it was to dangerous to fly the crew out there so much, n then edited and put the chicago back drop in after filming.
The Africa episodes which were supposed to taske place in the Congo in previous seasons were filmed in Hawaii. The recent epis about Dafur at the end of this season were filmed in the Kalahari desert in South Africa. They used locals as extras.
Although ER is mostly filmed in the Warner Studios in Burbank California (Holywood,LA), they do a lot of location work and most of the out of County General epis are filmed on location. Also they go regularly to Chicago to film outside scenes. The hospital is a studio construction, as is the ambulance bay, railway etc, all filmed on the Holywood lot, but those scenes by the Lake, or in the main square are all filmed in Chicago.
I hope that helps. I think my info is right, but I'm sure someone will correct it if it isn't.