Henryk Sienkiewicz's Mound, located approximately 1.5 km from the center of Okrzei; As a tribute to Henryk Sienkiewicz, a mound was built in Okrzeja in the years 1932–1938, thanks to the efforts and commitment of many Poles. Approximately 8,000 were used for its construction (base diameter 45 m, height 15 m). m3 of soil, which was sent even from America and many other places related to the writer. On its top, a commemorative stone with the inscription "Henryk Sienkiewicz 1938" was placed, which currently stands at the base of the mound. In 1980, in place of the commemorative stone, a white marble bust of Sienkiewicz was erected, designed by the Siedlce artist Marian Gardziński