Western Asia the Mediterranean Sea. To the north, the region is delimited from Europe by the Caucasus Mountains, to the southwest, it is delimited from Africa by the Isthmus of Suez, while to the east, the region adjoins Central Asia and South Asia. The Dasht-e Kavir and Dasht-e Lut deserts in eastern Iran naturally delimit the region somewhat from Asia itself. Three major tectonic plates converge on Western Asia, including the African, Eurasian, and Arabian plates. The boundaries between the tectonic plates make up the Azores-Gibraltar Ridge, extending across North Africa, the Red Sea, and into Iran. The Arabian Plate is moving
East Africa main goal on the Swahili coast was to take control of the spice trade from the Arabs. At this stage, the Portuguese presence in East Africa served the purposes of controlling trade within the Indian Ocean and securing the sea routes linking Europe to Asia. Portuguese naval vessels were very disruptive to the commerce of Portugal's enemies within the western Indian Ocean and were able to demand high tariffs on items transported through the sea due to their strategic control of ports and shipping lanes. The construction of Fort Jesus in Mombasa in 1593 was meant to solidify Portuguese hegemony