crucial
decisive or critical, especially in the success or failure of something
desert
a dry region that receives little rainfall and cannot support much vegetation
Eurasia
the combined continent of Europe and Asia
landform
a physical feature of the Earth's surface, such as a mountain, peninsula, or desert
mainland
the largest part of a continent, country, or land, in contrast with surrounding islands
peninsula
a piece of land almost surrounded by water or projecting out into a body of water.
plateau
a large area of elevated land that is relatively flat