Bohemia, much more truly than Switzerland, is the heart of Europe, set about equal distances from all the great seas, a marked physical unit cut off by forested mountains, and yet with easy access to those seas by the Saxon and Moravian, the Austrian and the Magyar gates, holding the balance between the northwestward-flowing Elbe and the southeastward-flowing Danube, for centuries a focus of political and ethnic interests and today one of the most important industrial areas of the world.