Irulegui castle is located on the Sierra de Aranguren in the municipality of Laquidáin.
During the Iron Age it there was a castro de los Vascones. This pre-Roman fort was destroyed around 76 BC. as a consequence of the rebellion.
Although there are legends that suggest the existence of the castle (or, at least, of a defensive structure in this place) during the Almanzor raids in the 11th century, the first reliable documents of the castle dates from the late 12th century.
In 1416 the castle was modernized, adding a triangular structure to the front. In 1494, the kings Catalina and Juan III (Juan de Labrit), agreed its destruction before the push of the Beaumonteses, who controlled the fortress, and consequently, the Pamplona Basin.
References:The Church of St Donatus name refers to Donatus of Zadar, who began construction on this church in the 9th century and ended it on the northeastern part of the Roman forum. It is the largest Pre-Romanesque building in Croatia.
The beginning of the building of the church was placed to the second half of the 8th century, and it is supposed to have been completed in the 9th century. The Zadar bishop and diplomat Donat (8th and 9th centuries) is credited with the building of the church. He led the representations of the Dalmatian cities to Constantinople and Charles the Great, which is why this church bears slight resemblance to Charlemagne's court chapels, especially the one in Aachen, and also to the Basilica of San Vitale in Ravenna. It belongs to the Pre-Romanesque architectural period.
The circular church, formerly domed, is 27 m high and is characterised by simplicity and technical primitivism.