Wyszków is a town in northeastern Poland with 26,500 inhabitants (2003). It is the capital of Wyszków County (Polish: powiat wyszkowski). Wyszków is in the Masovian Voivodeship (since 1999); previously it was in the Warsaw Voivodeship (until 1975) and the Ostrołęka Voivodeship (1975–1998).