Myszyniec - a town in the Mazowieckie Province, Ostrołęka County [3] [4]. It is situated on the Rozoga river. The seat of the town-rural commune of Myszyniec.
The city is located in Mazovia, in the historic Łomża region [5]. Myszyniec was granted town charter around 1798, was degraded on June 1, 1869 [6], and was re-granted town privileges in 1993 [7]. In the years 1975–1998, the town administratively belonged to the voivodeship Ostrołęka. Myszyniec is considered by many to be the capital of Kurpie.