The castle of Gresti or Pietratagliata is located near the village of Aidone. Its current condition is that of ruin even if well legible in the forms that are composed mainly of a mighty tower full and a series of rooms ingrottate. The first historical news documented dating back to the 14th century. The castle stands on a high rocky ridge of sandstone. The central part, the spur higher, has been used by man for its strategic position as a control station and defense. In fact the castle constitutes an outpost or a fortress of sighting for the control of a vast territory, connoted by important streets of communications which from the eastern coast is addentravano toward the center of Sicily dominated by settlements which Morgantina, Enna, Agira.
The structure extends over four levels: on the first level, which is also the oldest to be found in the rural houses and a large cave which opens with a loggia south and with a window and loggia and north. At the second level from which also begins the tower full and part the scale dug in the rock, there are two local: an input and a room with window delimited by benches in masonry. At the third level, the second floor where you find the environments 'noble' representation, there are four rooms dug in the rock and other in masonry. The fourth level is present an environment with entrance portal which would suggest a chapel and a cistern to collect rainwater. A mention deserves the high tower full, firmly anchored to the rock, visible at large distances. Has walls from compact surfaces, underlined by sharp built in blocks of stone perfectly squared; access to the terrace of the tower was allowed by a beautiful spiral staircase, with steps of basalt, placed in the corner of the south-east.
For the structure and for some particular aspects, the castle may not have had the function of an aristocratic residence, but was certainly a fortress of sighting within the valley of Gornalunga that, from the earliest times, has made a connection between the Ionic coast and the interior. The presence of numerous castles like (some today recognizable only by the toponymy) suggests plausible to assume that the castle had inserted inside a network of optical signals, defined anciently fani or fires, which allowed to rapidly transmit a signal even at a great distance.
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.