As a geographic feature, the Alps literally overshadow other landform regions. Just over 28% of Austria is moderately hilly or flat: the Northern Alpine Foreland, which includes the Danube Valley; the lowlands and hilly regions in northeastern and eastern Austria, which include the Danube Basin; and the rolling hills and lowlands of the Southeastern Alpine Foreland. The parts of Austria that are most suitable for settlement - that is, arable and climatically favorable - run north of the Alps through the provinces of Upper Austria and Lower Austria in the Danube Valley and then curve east and south of the Alps through Lower Austria, Vienna, Burgenland, and Styria. Austria's least mountainous landscape is southeast of the low Leithagebirge, which forms the southern lip of the Viennese Basin, where the steppe of the Hungarian Plain begins.