La Hougue des Geonnais is a passage chamber from the Neolithic age. It is today largely ruined by quarrying prior to the initial excavation in 1929. There is no capstone anymore. At that time the chamber was found to have a paving of pebbles and a large quantity of pottery fragments were disguarded in the spoil heaps. Excavation between 1985 & 1990 revealed a chamber that was probably constructed in two phases. A D shaped chamber being built first and then later extended to its current form. In 1990 some of the main chamber's missing uprights were replaced by dated, modern grantite blocks. A vast number of finds included pottery, flint scrapers, arrowheads and broken querns.
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.