The concept of international trade was born in the ancient Mediterranean, which provided the perfect set of circumstances needed to produce an intricate trading system whose influence can still be seen in present-day economic practices. The ancient Mediterranean was home to a diverse range of cultures and landscapes, encompassing deserts, forests, islands and fertile plains. Different natural resources were available in different geographical areas, and with the advent of sailing ships around 3000 BCE, people were suddenly able to travel much further afield than ever before. This created an opportunity to trade local resources in international markets in exchange for exotic goods not available at home. At the same time, this shift in Mediterranean trade from a local to international scale was a catalyst for immense social, political and economic changes that helped to shape the course of Western Civilization as a whole. Ancient trade in the Mediterranean brought cultures into increasingly close contact with one another, and just as in the globalized world today, these cross-cultural influences came to shape the development of belief systems, languages, economics, politics, and art throughout wide expanses of land. Over the centuries, the profits generated from trade helped establish wealthy nations and fuel economic development across the sea. By taxing imports and exports, governments could afford large infrastructure projects, like the construction of roads and harbors, which in turn helped to further increase trade and wealth. As a result, wars were fought for control of important trade routes and to maintain access to crucial commodities such as grain and precious metals. Economics became a primary consideration when establishing government policies and dealing with international relations. Some cities, most notably Rome and Athens, even built empires on the back of their mercantile success.