It is a small area around Zerbst / Anhalt . The area is delimited by the Fuhne , the two streams and the hollow at Mukrena . The Gau was under the influence of the Slavs . Gero prevailed. The responsible archpriest had his seat in Zörbig . Due to its small size, the Gau is regarded as the Untergau of the Gaus Serimunt and ultimately merged into the margraviate under Konrad von Wettin .