Seasonal winds on the Indian Ocean provided opportunity for ancient sailors to move from port to port.
Indian Ocean Trade Networks
A network of tradings zones in the Indian Ocean developed between 300 BC and AD 300. This network not only generated awareness of the larger world in the NT period, but introduced luxury goods to those who could afford them.
The Indian Ocean: Position and Place
I'm thinking big about a great sea south of the Biblical Heartland. Its contours are less familiar to many, but its influence is significant.