Giżycko is a town in northeastern Poland with 29,796 inhabitants 2004. It is situated between Lake Mamry and Lake Niegocin in the region of Masuria, and has been within the Warmian-Masurian Voivodeship since 1999, having previously been in the Suwałki Voivodeship 1975–1998. It is the seat of Giżycko County.