Although miles from the majority of Round Tower Churches in East Anglia, St Mary’s in Great Shefford was probably built for the same reasons! Flint was the available material, and a round tower does not need dressed stone for quoins. This tower is in three stages, divided by two string courses. It is all made of flint rubble, built at the same time as the nave in the 13th century. There is a large stone-framed lancet facing west on the ground floor, with its arch restored. Above this in the next stage is another, smaller lancet, one of three at this level. As they are below the nave ridge level, they could not have been belfry openings. The top stage is octagonal and has four belfry openings with Y tracery and hood moulds. The parapet has battlements. The nave and chancel are one width, and covered with a continuous roof of red tiles, except over the north chancel where a cross is picked out in grey tiles. The chancel still has some of its 13th century lancet windows, though the east window is now a large 15th century one. Some stone-work of the former lancet arrangement survives below it. The “transitional” south doorway has a pointed arch (13th century), but the outer arch has the zig-zag ornament of the 12th century. The shafts supporting this arch have beast-head capitals, again reflecting the 12th century, so probably the doorway is around 1200. There is a 19th century painted text above the door.

The tower arch is pointed and has three chamfered mouldings. Round the arch and above it are more 19th century paintings of texts. Beneath the tower stands the tub font, which is covered with four bands of scrolly foliage carvings. This carving could make the font date back to the 11th century! Near the north doorway is an elaborately canopied stone niche, now containing a modern figure of the Good Shepherd. High on the east wall of the chancel are medieval paintings of the Annunciation, St Gabriel on the north and the Blessed Virgin Mary on the south. Below is the reredos from the 20th century, showing the Nativity on the central panel, flanked by the visits from the Magi and the Shepherds.