In June and July 2018, archaeological research was done on the site of Pakrac – Stari Grad, in the very centre of the town of Pakrac. The research focused on the structure that was found in trench 1 in the previous year: the remains of a Gothic chapel of the Order of Saint John. It was confirmed that the remains originated from at least two construction phases. In the first phase, which was dated to the 13th century on the basis of architectural features, the chapel was built from finely cut stones, and the walls were reinforced by supports on the outside and lesenes on the inside. In the south-west corner, there was the entrance from the chapel to the spindle stairs. The eastern, final wall of the chapel is still outside the trench, so that its complete ground plan is still unknown. Other interesting details have been preserved, such as the slots for bolts securing the door of the main entrance to the chapel and the staircase door, as well as the bases of the pilasters leaning against the lesenes. The other certain construction phase of the chapel is best represented by the discovered bases of the portal, which were put against the front wall of the Gothic chapel around the year 1500. At the same time, all the walls were made almost twice as thick. This leads to the hypothesis that the structure was turned into a “fortress church”, with walls 280–290 cm thick, which would not be strange considering the approach of the Ottoman threat. The Pakrac fortress, with round towers on the corners of an irregular pentagon, seems to have been built more or less at the same time. It was also in the 15th century that builders laid the brick floor preserved in the west part of the nave, where there are traces of the only grave found so far. A post-sacral purpose of the structure is confirmed by the numerous finds of animal bones.