During the 6th century AD a small community of monks settled on the Inishkeel island. Their religious leader was Saint Conall Cael, from whom the island later derived its name. During the following centuries Inishkeel was a traditional destination of pilgrimages. Remains of the church and the connected buildings as well as some carved stones can be seen on the island. For its artistical and archeological importance the island was declared National Monument. A bell known as St Conall Cael's Bell remained on Inishkeel up to the 19th century and was then acquired by the British Museum.
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.