Ciechanów is a city in north-central Poland. From 1975 to 1998, it was the capital of the Ciechanów Voivodeship. Since 1999, it has been situat…Ciechanów is a city in north-central Poland. From 1975 to 1998, it was the capital of the Ciechanów Voivodeship. Since 1999, it has been situated in the Masovian Voivodeship. As of December 2021, it has a population of 43,495.