The parish church of Ottery St Mary in east Devon is notable for its age, the oldest section dating from the 13th century, its large size, and the beautiful interior, resembling a cathedral in layout and grandeur. Even when first constructed the church was more elaborate than most due to its patronage by the wealthy bishops of Rouen Cathedral, who had owned the local manor since before the Norman conquest, and the building was enlarged in the 14th century after establishment of a collegiate foundation, run by a group of priests - an institution similar to a monastery though not of the Catholic faith, hence the church was unaffected by the 1539 Dissolution, and has survived intact, the only other significant modifications being an extension in the early 16th century, and a full restoration between 1849 and 1850.
St Mary's Church has a relatively secluded location on the north side of town, close to open countryside and the River Otter, and it is open to visitors every day, with no charge for entry, though donations are appreciated. Besides the spectacular architecture, mostly of the Early English Gothic style, highlights include ornate and colourful ceiling vaulting, several medieval tombs and monuments, and a 14th century astronomical clock.
The present church at Ottery was completed in 1260 under the supervision of Walter Branscombe (died 1280), Bishop of Exeter, and incorporates several elements from the design of the cathedral there. The chancel and the two transepts survive from this period. Major reconstruction of the church was carried out in the 1340s by John Grandisson, also Bishop of Exeter, including rebuilding of the nave, and addition of the Lady Chapel at the east end and two chantry chapels either side of the chancel. The final major changes, around 1520, were instigated by Cecily Bonneville, Countess of Dorset; principally expansion of the north nave aisle, complete with elaborate, fan-vaulted ceiling and pendant bosses. Soon after this, in 1545, the collegiate foundation was closed, and the building became a regular parish church, run by governors. The subsidiary buildings of the college, such as the cloisters, library and chapter house, were soon demolished.
Visitors enter the church through a porch on the south side of the nave, which has five bays and is lined by narrow aisles, delineated by slender columns. Between two opposite pairs of columns are the decorative canopy tombs of Otho Grandisson (died 1359, younger brother of the bishop), and wife Beatrix. Above the nave is a high, vaulted ceiling, painted white, supported by red and blue ribs, intersecting at gold bosses, decorated with shields and coats-of-arms . The north aisle of the nave adjoins the broad, vaulted corridor added by the Countess of Dorset in the 16th century, in one corner of which is the elaborate, life-sized effigy of governor John Coke, died 1632. The crossing and the two transepts have similarly colourful vaulting, with a different pattern of ribs and bosses. Each transept is topped by a square tower, an uncommon arrangement for a parish church, the usual design involving a single tower, above the crossing. The south transept contains the astronomical clock, contemporary with and similar in design to others at Exeter Cathedral, Wimborne Minster and Wells Cathedral, and a tiled mosaic floor, installed during the 1849-1850 restoration. The crossing leads to the chancel, unusual for being longer than the nave (with six bays); at the east end is the altar, beneath an ornate reredos, a partial replica of the 14th century original. The chancel is also lined by aisles, which meet at the far side at the entrance to the Lady Chapel, which is lit by eight narrow, lancet windows containing Victorian stained-glass. Other features of note in the church include several medieval brasses, along the south chancel aisle, an eagle lectern purchased by Bishop Grandisson, and an array of misericords on the wooden stalls in the chancel.