St. Trinity Church in Strzelno is built from granite blocks. It's a three-aisle basilica with a transept, chapels and two towers from the west side. Besides the apse and the gallery, the original interior had a wooden ceiling.

Great pieces of Romanesque art are 4 columns from the end of the 12th century carved out in sandstone. Each of them has a picture with 18 figures on it, with examples of human weaknesses and sins on their left side and with examples of virtues on the right side. On the choir walls there are other, partly unveiled, Romanesque columns with smooth trunks. Baroque-style dominates in the Church interiors.

The Holy Cross altar decorated with 658 relics is the Church’s precious historical monument.