Unterharz is a former Verwaltungsgemeinschaft ("collective municipality") in the district of Harz, in Saxony-Anhalt, Germany. It was situated in the eastern part of the Harz, south of Quedlinburg. The seat of the Verwaltungsgemeinschaft was in Harzgerode. It was disbanded on 1 August 2009.
The Verwaltungsgemeinschaft Unterharz consisted of the following municipalities:
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