What role did the cities of mogadishu and mombasa play in the economic life of east africa?

Mombasa is a city on the coast of Kenya. It is the country's second largest city next to it's capital, Nairobi. It is a regional cultural and economic hub and a tourist hub as well. It has an extra large port and an international airport too. Its strategic location had resulted to several countries trying to control Mombasa.
Mogadishu is the largest city in Somalia and the nation's capital. Just like Mombasa, it is geographically possible to trade in this place. In fact, it has been a significant trading port over the centuries.
Both of them greatly affected East African Economy due to their geographical location which is coastal.
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