The ruined church survives, also below ground remains of the cloistral buildings, Priory and parochial cemetery. The exact extent of the Priory Precinct is unknown.<16>

RCHME survey 1922: St Botolph's Priory was founded at the close of C11; this was the first house of Augustinian Canons in the country. The priory was suppressed in 1536 and mostly destroyed except the nave, or such part as was parochial. The building was entirely ruined in the siege of 1648. Apart from minor details, the whole of what remains is of the mid C12. Seven bays remain from the nave which probably once extended further E. The W front extends as one composition the full width of the nave and aisles and was flanked by the two western towers. The N tower is ruined to near the ground while the lowest stage survives on the southern tower. Of the front itself, a fragment at the end of the S arcade rises to almost full height but the rest is ruined. The richly ornamented W doorway and the S aisle doorway largely survive but little remains of the N aisle doorway. The west front was richly decorated with window recesses and wall-arcading. Later features include C13 and C14 windows in the aisle walls. Nothing remains of the domestic buildings S of the church except the base of the N arcade wall of the cloister. A thick rubble wall incorporated in the house 'now' shop, No 37 Botolph’s Street is probably part of the entrance or gateway to the Priory. According to the RCHM glass in a case in the SW tower was found in excavations. There is a C14 niche in the first column from the E of the N arcade. In the N aisle, on the N wall, painted masons lines on plaster are probably C14. Remains of tile paving in the nave and aisles also recorded by the RCHM. RCHM has plates and plan of the church. <1>

Survey of St Botolph's Priory by Pevsner, 'The most important and impressive ecclesiastical monument of Colchester; the ruin of an Early Norman church of considerable size. St Botolph's was founded late in the C11 as the first British house of Augustinian Canons. What remains is a ruin, and the ruin only of the W front and the nave (108 ft long). Transepts and E end have completely disappeared. The church was built of rubble with plenty of Roman bricks, used in the walls as well as more consistently for dressings. The W front is broad; the two towers stand outside the aisles, not identical incidentally either in size or in shape. There are three portals; the middle one of four orders of columns, the capitals with finely intertwined scrolls or decorated scallops (badly preserved), the arches with much zigzag. Above the portals, but with the middle one cutting into it, two tiers of intersected arches without capitals. The principal W window was circular, and the earliest major round window in England. The facade must date from after the mid C12. Nothing survives of the upper parts of the towers. Inside the facade a passage, carried on a tunnel-vault, runs on the first floor from the tower to the other, open to the nave. The nave has mighty circular piers (5ft 8" in diameter), They have no proper capitals and support a gallery with un-subdivided openings as large as the arcade. The arches are single stepped and un-moulded on both sides. Flat pilaster strips stand on the circular piers to divide the bays of the gallery from each other. The aisles were groin vaulted. The building is immensely impressive as a ruin. To the S of the church, foundations of the N wall of the cloister'.<2><22>

DOE survey of St Botolph's Priory Church ruins. Grade I. The ruins of the great mid C12 conventual church of the Priory of St Botolph, founded at the beginning of the century as the first house of Augustinian Canons in England. It was built almost entirely with stone and brick taken from Roman buildings. There are great circular columns in brick to the nave, and the west front is particularly fine, with curious interlacing arcades in brick. The church survived the suppression of the Priory in 1536 as it had been the parish church of St Botolph's for some time. It was ruined in the siege of Colchester in 1648.<3>

A watching brief was held St Botolph's Church. Negative evidence. The site was visited in retrospect after the building works had finished because an archaeological condition was omitted from the planning consent (Carl Crossan 27/01/2000 pers. comm.).<4>

In 1991 a selective investigation to the east of the standing remains of the nave located the south transept and square east end of the priory church. Excavation of deep post-medieval disturbance at the east end of the church yielded a glimpse of an underlying late Roman building. The archaeological investigation was the first stage in an improvement scheme for the monument to include landscaping and the marking out of major features in the eastern ground plan of the priory church.<5>

A stone-by-stone drawing was made of the western elevation of St Botolph's priory in advance of repair work in 1989-1990.<6>

Selected images held by Colchester Museum: Ink drawing of St Botolph's Priory.<7> Pencil drawing of St Botolph’s Priory, Colchester.<8> Watercolour painting of St Botolph's Priory.<9>

Documentary evidence records that a church existed before the foundation of the Augustinian Priory, between c.1093 and 1100.<10>

The building is managed by Colchester Borough Council under a Guardianship agreement with owners English Heritage. A detailed condition survey was prepared by English Heritage in 1995.<11>

A detailed description of the monument is provided in the Schedule of Ancient Monuments entry.<12>

Trial trenching in 1986 to the north-east of the standing remains of the nave of the Priory church revealed traces of the previously unrecorded north transept (ECC977).<13>

Scale drawing by Major Bale showing a stretch of rubble wall, thought to belong to the St Botolph's Priory precinct, surviving as part of the boundary between 37 St Botolph's Street and building to the North. The surviving rubble wall was no more than 3ft by 3ft and stood about 3ft in from the modern frontage. The modern street is divided between 37 & 37a and it is not clear whether the numbering has been changed since 1898.

Speed's 1610 map of Colchester shows the priory church intact, within an enclosure fronting Priory Street. There is a ruined building to the outside/adjoining the southeast corner, labelled as ' The Nunnory'. It is possible that these would have belonged to the infirmary. There are also buildings to the south of the priory with a gatehouse and precinct wall, on to Magdalen Street, conceivably outbuildings belonging to the priory sold off after the dissolution. <15>

A number burials have been found close to the Priory Church (all to the east/north-east), which are likely to be associated with it. Hull records nine skeletons to the east of the Priory, discovered in 1939 (MCC1396-MCC1404) and also other inhumation burials to the north of the Priory, on Priory Street (MCC9296).<17><18> Trial-trenching in 1986, to the east of the church, produced two inhumation burials (MCC2067-2098).<19> Two inhumations were discovered in a footings trench in 2000.<20> A further two E-W aligned inhumations were defined in an evaluation trial trench in 2014.<21>