The Cape of Good Hope had proven to be an insurmountable obstacle to western exploration in the Indian Ocean until the combination of better maritime technology and successful navigation saw Vasco Da Gama round this promontory in the late fifteenth century. Subsequently, Portuguese fleets soon followed suit. They began to look for places along the eastern coastline of Africa that could serve as both strategic centers in their maritime expansion as well as safe havens for their vessels. While they desired to reach India and the rich trading grounds of the Spice Islands, China and Japan, they also realized that they needed to be careful in not expanding too quickly. Consequently, the Portuguese made use of the harbor of Mozambique, which could supply the vessels that were making their way further east. Although Portuguese presence was consistent here during the sixteenth and early seventeenth century, they did not exert or possess much control beyond the coast. In part this was because of their lack of relative strength and because they were focused on trade elsewhere. Nevertheless important missionaries like Matteo Ricci did stop here on their way to China.