Architecturally, St Mary's Church was one of the most ambitious churches in the county. It is in the Decorated style with a prominent, integral, tower. The church was originally dedicated to St Leonard, until the mid-nineteenth century restoration. The porch, of the fourteenth/fifteenth centuries, has buttresses which display gargoyles and pinnacles.
The interior contains interesting, nineteenth-century, stained glass, including The Good Shepherd by Kempe & Co of 1930–31.
Next to the church stands The Procurator's House, a sixteenth house, now ruined, which belonged to the vicarage of Magor.
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.