How the Silver Trade Started | Modern World History 8 of 30 | Study Hall 

It's easier for ships to sail in water than over land.

Not just easier to move goods over sea but by hugging the coast, it was often safer than going over land where theft on trade routes was much more common

The very north of Africa wasn't an option since the Ottomans controlled it, central Africa was also a no-go because of the Sahara and malaria and down in southern Africa there were diamonds so they went to southern Africa by sea.

@@facelessman7733 Yeah but I doubt that's what he meant.

@@EuropeanQoheleth isn't it though? the point is that with the technology & infrastructure of the time it was easier to transport large amounts of goods over sea.