With the development of maritime trade in the second century B.C., the rival kingdom of Saba began to cultivate an alternate source of aromatics in Ethiopia and exploited the quicker and cheaper Red Sea routes to counter the Hadrami monopoly. By the first century A.D., the Roman and Greek traders had begun to arrange their own shipments of goods at the now lost Yemeni port of Muza. Seaborne traffic was now routed to the Western Coast of the Red Sea, to the Egyptian port of Clysma, which was connected to the Nile by the newly constructed via nova Traiana. This replaced the Nabatean port of Leuke Kome on the eastern coast as the principal destination of goods shipped by sea from southern Arabia. Travel by sea, however, was not easy.
Coral reefs divide the Red Sea into channels of which only the central one is navigable.
On the Arabian Coast shallow water prevented the establishment of deepwater ports for large vessels, and reefs and shoals on the Egyptian side obstructed the approach to the shore. Here Myos Hormos, Leucos Limen and Berenice were the only safe harbors. The discovery of the monsoon winds in the first century A.D. enabled boats to sail from Egypt to India and back in one year. Overland routes were expensive, time-consuming, and unsafe for fragile items. Moreover, bulk goods were inconvenient to transport by camel and the roads were primarily tracks in the sand.