Church of St. Adalbert was created in the style of the mazovian gothic after 1546, thanks to the foundation of Benedictines from Płock. The construction of the church could not begin until the works at the Płock Cathedral were completed, from which bricklayers and building materials from the chapter brickyard were transferred. By 1822 Benedictine monks from the monastery in Pułtusk took care of him. In 1618 the tower gables were transformed. The church was renovated several times in the 19th and 20th centuries when a neo-gothic porch was added to the southern façade.
The building is a three-nave basilica with an elongated, straight ended chancel and a five-storey tower on the facade. The four-span nave is based on a plan close to rectangular and is covered by a common roof with a three-span chancel, equal to the width and height of the main nave. The northern aisle was extended for a chapel, sacristy and vestibule with the burial crypt of the Milbergs. Adjacent to the southern aisle is an outbuilding with a staircase to the tower and a small neo-gothic vestibule. The corners of the nave, the chancel and the tower are covered with fault buttresses, and the aisles are divided by diagonal buttresses. The eastern elevation of the chancel is crowned with a stepped gable filled with rows of semicircular blendes. At its center is a walled window in the form of a deep niche closed with a full bow. The interior is covered with a ceiling.
The unusual structure of the church in Szczepanków is the west tower in which rooms heated with fireplaces were placed (probably intended for the Benedictines from Płock managing the church) and the western gallery. This building resembles castle or city towers, although it had no defensive features. The lower floor received on both sides quite deep niches and the main front entrance to the church. The interior of the temple was connected to the tower first floor by means of stairs hidden in the annex at the front wall. The first floor of the tower was occupied by a small room opened into the interior of the church with a large, semi-circular arcade and illuminated by two windows from the west and one from the south. It was warmed by a fireplace. Stairs in the thickness of the north wall led to the upper floor. From their platform, in the north-west corner of the tower, a short diagonal corridor was placed in the thickness of the buttress, ending with a currently walled up portal. It probably served to preach to people gathered in the cemetery. The next floor also housed a room illuminated by three windows and equipped with a fireplace. Stairs in the thickness of the northern wall, and then the eastern wall led from it to the church attic from which you could enter the third floor of the tower, without a fireplace, but illuminated by two windows. Finally, the stairs from the attic in the north wall led to the top fourth floor of the tower, with six window openings. This floor was intended for bells.
Kunkel R.M., Architektura gotycka na Mazowszu, Warszawa 2005.
Żabicki J., Leksykon zabytków architektury Mazowsza i Podlasia, Warszawa 2010.