File:Blyth, Ss Mary & Martin's church (49226540803).jpg

This Priory church dates back to the eleventh century, and was once much larger than its current state. It was founded in 1088 by Roger de Builli, a Norman Baron who accompanied William the Conqueror in 1066. It was built to French designs and given to the Benedictine Abbey of the Holy Trinity in Rouen.

There is a western tower, vaulted nave (of seven bays originally, now five) with north and south aisles, chancel and south porch. Originally there was a transept with apsoidal chapels and central tower which have now gone. The Norman south aisle was removed at the end of the twelfth century and a new one was built, of larger size. The two arches linking it, which are behind the altar were part of the south transept. The south porch was moved to its current position – quite some undertaking. The north aisle has a crude groined ceiling The interior of the church was originally brightly painted, some traces of which remain.

The original Priory church extended to the east beyond its current boundary and ended in a chancel with an apse along with several chapels off the transepts. In the fifteenth century the two halves of the church passed into separate ownership, and a wall was built to separate the Priory Church from the Parish church. The existing western tower was built at this time. At the dissolution, the Priory lands were confiscated and in 1635 the land was bought by the Mellish family who demolished the eastern end of the Priory.

The fifteenth century eastern wall was painted with a large "doom" depicting the last judgement, although this was covered over after the Priory was dissolved.

The present screen dates from the fifteenth century and the lower panels are painted with various Saints.

The chancel contains a damaged effigy of a Knight wearing a heaume, or “Coal-scuttle” helmet, which dates the tomb to between 1190 and 1240. It is thought to be Percival or Thomas Fitzwilliam.

There is also a monument to Edward Mellish d.1703, which was originally situated under the doom painting and moved to its present position in 1885.

The font dates from the seventeenth century and is adorned with cherub’s heads. There are several stained-glass windows, with the west window being by Kempe. There is no east window.

At the west end of the church there are several hatchments belonging to the Mellish family who owned Blyth Hall.

The church has a small two manual pipe organ.