Poland

Greater Poland Voivodeship

• Ostrów Wielkopolski, a town in Greater Poland Voivodeship (west-central Poland)
• Ostrów, Greater Poland Voivodeship in Greater Poland Voivodeship (west-central Poland)

Kuyavian-Pomeranian Voivodeship

• Ostrów, Brodnica County in Kuyavian-Pomeranian Voivodeship (north-central Poland)
• Ostrów, Tuchola County in Kuyavian-Pomeranian Voivodeship (north-central Poland)

Lesser Poland Voivodeship

• Ostrów, Proszowice County in Lesser Poland Voivodeship (south Poland)
• Ostrów, Tarnów County in Lesser Poland Voivodeship (south Poland)

Lublin Voivodship

• Ostrów Lubelski, a town in Lublin Voivodship (east Poland)
• Ostrów, Biała Podlaska County in Lublin Voivodeship (east Poland)
• Ostrów, Gmina Dorohusk in Lublin Voivodeship (east Poland)
• Ostrów, Gmina Wojsławice in Lublin Voivodeship (east Poland)
• Ostrów, Kraśnik County in Lublin Voivodeship (east Poland)
• Ostrów, Tomaszów Lubelski County in Lublin Voivodeship (east Poland)
• Ostrów, Lubartów County in Lublin Voivodeship (east Poland)

Lubusz Voivodeship

• Ostrów, Lubusz Voivodeship in Lubusz Voivodeship (west Poland)

Łódź Voivodeship

• Ostrów, Łask County in Łódź Voivodeship (central Poland)
• Ostrów, Łowicz County in Łódź Voivodeship (central Poland)
• Ostrów, Opoczno County in Łódź Voivodeship (central Poland)
• Ostrów, Gmina Aleksandrów in Łódź Voivodeship (central Poland)
• Ostrów, Gmina Grabica in Łódź Voivodeship (central Poland)
• Ostrów, Sieradz County in Łódź Voivodeship (central Poland)
• Ostrów, Gmina Ozorków in Łódź Voivodeship (central Poland)
• Ostrów, Gmina Zgierz in Łódź Voivodeship (central Poland)

Masovian Voivodeship

• Ostrów, Garwolin County in Masovian Voivodeship (east-central Poland)
• Ostrów, Kozienice County in Masovian Voivodeship (east-central Poland)
• Ostrów, Mława County in Masovian Voivodeship (east-central Poland)
• Ostrów, Otwock County in Masovian Voivodeship (east-central Poland)
• Ostrów, Sierpc County in Masovian Voivodeship (east-central Poland)
• Ostrów Mazowiecka, a town in Masovian Voivodship (east-central Poland)

Podlaskie Voivodeship

• Ostrów, Gmina Poświętne in Podlaskie Voivodeship (north-east Poland)
• Ostrów, Gmina Suraż in Podlaskie Voivodeship (north-east Poland)

Silesian Voivodeship

• Ostrów, Lubliniec County in Silesian Voivodeship (south Poland)
• Ostrów, Myszków County in Silesian Voivodeship (south Poland)

Subcarpathian Voivodeship

• Ostrów, Przemyśl County in Subcarpathian Voivodeship (south-east Poland)
• Ostrów, Jarosław County in Subcarpathian Voivodeship (south-east Poland)
• Ostrów, Przeworsk County in Subcarpathian Voivodeship (south-east Poland)
• Ostrów, Ropczyce-Sędziszów County in Subcarpathian Voivodeship (south-east Poland)

Świętokrzyskie Voivodeship

• Ostrów, Busko County in Świętokrzyskie Voivodeship (south-central Poland)
• Ostrów, Opatów County in Świętokrzyskie Voivodeship (south-central Poland)
• Ostrów, Kielce County in Świętokrzyskie Voivodeship (south-central Poland)
• Ostrów, Włoszczowa County in Świętokrzyskie Voivodeship (south-central Poland)

Warmian-Masurian Voivodeship

• Ostrów, Warmian-Masurian Voivodeship in Warmian-Masurian Voivodeship (north Poland)

West Pomeranian Voivodeship

• Ostrów, West Pomeranian Voivodeship West Pomeranian Voivodeship (north-west Poland)

Belarus

• Astraviec, town in Belarus
• Vostrava, village in Belarus where the Astrava Treaty was signed

Lithuania

• Astravas, suburb of Biržai, Lithuania