What parts of the world and continents were known to ancient Greek scientists?

Despite the fact that the Greeks were skilled seafarers and travelers, they knew only two continents (Eurasia and Africa) and three parts of the world (Europe, Africa and Asia). In ancient times, ships were not large enough to take a lot of supplies for long sea voyages. People swam mostly close to the coast and often stopped to restock. Therefore, new continents opened up to Europeans only in the Middle Ages, when large sailing ships appeared.