From Halopedia, the Halo wiki
In modern-day Mombasa, there is a district called "Liwatoni". This location is fully submerged by the 26th century, located some hundreds of meters WNW of Uplift Nature Reserve. Evidently, the district has been redesignated since the 21st century; this is the case with many other districts in the city as well, due to the fact that the coastlines and structure of the city have changed so dramatically.
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