Ojrzeń is a rural commune in the Masovian Voivodeship, located in the Ciechanów County. Its administrative seat, also named Ojrzeń, boasts a rich historical and architectural background. According to data from June 30, 2004, the commune had a population of 4,420, reflecting its intimate and close-knit character. Ojrzeń covers an area of 123.11 km², of which 66% is agricultural land and 25% is forested. The commune constitutes 11.59% of the area of Ciechanów County, highlighting its significant role in the local structure. Within the commune, there are numerous village administrative units (sołectwa), such as Baraniec, Brodzięcin, Młock, and others, as well as villages without such status, indicating a rich and diverse settlement pattern. In the region, particularly in the village of Młock, one can find one of the most magnificent oak trees in Poland—Uparty Mazur (Stubborn Mazurian), which is approximately 500 years old and has an impressive circumference of 900 cm. This tree is not only a natural treasure but also a witness to the region's history. The Ojrzeń commune showcases remarkable biodiversity, attracting nature enthusiasts and tourists alike. An interesting aspect is the local population age pyramid, which may reflect demographic changes and the dynamics of the community. The commune borders other municipalities, such as Ciechanów, Glinojeck, Sochocin, and Sońsk, fostering cooperation and cultural exchange. With its history, nature, and cultural richness, Ojrzeń is a fascinating place on the map of Masovia.