Nicolaus Copernicus stayed in the local castle of the Warmian Chapter many times, in particular when settling settlers in the surrounding villages (Kumajny, Lubianka, Łajsy, Łoźnik, Miłkowo, Osetnik, Pełty, Pełty, Radziejewo, Wopy). He did so at the beginning of 1517, in October and November 1518, and in March 1519.
The castle which the astronomer visited, originally Gothic, was later rebuilt many times, and has remained in ruins since the years of World War II. Apart from the castle, in the town existing since 1312, there are also the remains of a Gothic Town Hall (in reconstruction) and the church of St. Peter and Paul the Apostles from the 14th century and a temple from the 17th century (currently the Greek Catholic church of St. Michael the Archangel). By the seminar there is the Missionary and Ethnographic Museum of Priests of Verbists.
The Green Velo East of Poland Cycling Trail runs through Pieniężno, where lovers of two wheels can ride a total of 395 km in the Warmian-Masurian Voivodeship and nearly over 1600 km in four others.