Central Austro-Bavarian dialects are spoken in Munich, Upper Bavaria, Lower Bavaria, southern Upper Palatinate, the Swabian district of Aichach, the northern parts of the State of Salzburg, Upper Austria, Lower Austria, Vienna (see Viennese language) and the Northern Burgenland).
There are noticeable differences in the language within the group, but changes historically occur along a west-east continuum. That means that the languages of Vienna and Munich are very different from each other, but the dialects of any two neighboring towns in between will be quite similar. However, due to influences of the corresponding political centers, discontinuous change is nowadays noticeable along the national border between Austria and Germany. Generally, Viennese has some characteristics differentiating it from other Austro-Bavarian dialects due to the influence of languages spoken by people moving to Vienna from many areas of Austria-Hungary during the 19th century.
A characteristic of Central Austro-Bavarian is the vocalization of l and r after e or i. E.g. the standard German viel becomes either vui (in Western Central Austro-Bavarian) or vüü (in Eastern Central Austro-Bavarian). The border between the western and eastern subgroups roughly coincides with the border between Bavaria and Austria.
In all subgroups, hard consonants such as p, t, k are softened to become b, d, g.