What made traveling by sea interesting in this era?

What is the relationship between mountains and rivers? What was the statue of Zeus holding in his left hand? Where is the thinnest sediment cover in the oceans? How rivers be saved? What animals did mission San Fernando rey de espana raise? What rivers flows through turkey Iraq and easternmost of the two magor mesopotamian rivers? Map of Ireland's rivers? How many countries does the river Po flow through? What is the most expensive stone in the Washington monument? Where is the Gulf of Mexico anoxic zone? Which forests do not have a distinct period of shedding leaves and therefore do not ever look bare? Who are the small statues representing on Liberty Island? Why were the rocky deserts east of Meroe so valuable? Compare the advantages and disadvantages of multi purpose river projects? Who did Percy find in the ocean in California? Are there more than one nile river? What is the meaning of the pacific ring of fire? Name two Inland seas that are located in Europe? What is the fine soil the nile deposits near its mouth? Eiffil tower is big of the world?