Trethevy Quoit is a well-preserved megalithic structure between St Cleer and Darite in Cornwall. It is known locally as 'the giant's house'. Like other portal structures of this type, Trethevy Quoit was originally covered by a mound. The remnants of this suggest a diameter of 6.5 metres. The remaining seven stones and the 3.7-metre long and 10.5-ton cover slab were inside the mound. At the upper end of the cover slab is a natural hole, which may have been used for astronomical observation. The group of horizontal stones is composed of a fallen back wall, two overlapping side wall stones, a front stone and a somewhat remote flanking stone. The special feature of Cornish portal graves is that by such stones sometimes a smaller partially closed area is created before the front end. Some stones have hole-like perforations as decoration. The front stone is often called an entrance stone, although in most portal structures this can not be moved. Trevethy Quoit is a rare exception here, because a small rectangular stone moving at the bottom right of the front allows access to the chamber, which is now opened only very rarely.
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.