Opoczno [ɔˈpɔt͡ʂnɔ] is a town in south-central Poland, in eastern part of Łódź Voivodeship (since 1999), previously in Piotrków Trybunalski Voivodeship (1975–1998). It has a long and rich history, and in the past it used to be one of the most important urban centers of northwestern Lesser Poland.