The success of agriculture in Europe is an issue of geography and technology. Europe has large areas of flat, arable land that may be utilized for farming. This is especially true of the Great European Plain. The Incas, on the other hand, were very limited in the amount of land they could use for agriculture. In fact, the Incas developed their own lands for farming, which required a great deal of labor and effort. Europe is also blessed with fertile river valleys that can be used for irrigation. The Incas did not have fertile valleys to plant crops. The landscape of Europe also permitted relatively easy travel so goods can be traded with other peoples. This brought wealth and a variety of goods that could be invested in further agricultural development. The landscape of the Incas was a challenge because of the steep mountains, the deserts to the west, and rainforests to the east. As far as domesticating animals, Europe's climate and geography support a much larger variety of animals than the harsh conditions that the Incas faced.