The former cathedral church at Dunblane is built around an earlier tower, which appears to have been free-standing when first built. This tower has four 12th-century levels, each separated from the next by an exterior stringcourse. Above these are two further levels which were built in the late-15th/early-16th century. The tower was entered by a doorway on the north side, which has worn capitals, bases, label and imposts; the shafts no longer exist. The interior face of the doorway is plain, with a taller opening, it's arch formed of simple voussoirs. Inward from this and lower, is the N face of the doorway proper, with plain lintel stone and coursed stonework above it. The ground-floor level has a recess in the E wall, which may have served as an altar. The label arch over it is carved with a series of lozenges. Inserted into the ground-floor ceiling at some later time is a stone barrel vault. Access to the upper levels of the tower is via a spiral staircase in the interior SW corner. The top story of the 12th-century tower has an arched opening on each face. The outer, exterior arch of each is plain, but further into the depth of the arch are two smaller arches resting on a shaft and associated features. On the exterior, no other decorative features occur. Following the Reformation, although the eastern part of the church was preserved, along with the tower, the nave was allowed to became derelict, and by 1622 was said to be roofless. Restoration work and some reorganisation was undertaken on parts of the church structure in the early- and late- 19th century. During this time a wooden barrel vault was built over the nave and a new roof erected.

Two early cross slabs found in 1873 attest to a religious importance for the site as early as the 8th or 9th centuries. The first bishop of the newly established cathedral of Dunblane appears to have been Bishop Laurence, the earliest surviving record for whom is a papal letter sent to the bishops of Scotland on 27 February 1155. A single entry for ‘M. de Dunblan’ about 1155 has also been frequently noted as well, but this reference remains enigmatic. Bishop Laurence continued to appear in documents of the 1160s and very early 1170s. Two further bishops are recorded in the 12th century, following Laurence: Symon (or Symeon) and Jonathan. Curiously, in a later confirmation charter of 1239 by Bishop Clement, the early bishops of Dunblane are listed beginning with Symon, with no mention of Laurence (Reg. Cambuskenneth, no. 126). Gervase of Canterbury, writing about 1207 (copied in the mid-13th century), lists the bishopric of Dunblane as Culdee. In a confirmation grant, probably by the enigmatic Bishop William de Bosco (early 13th century), two witnesses of Dunblane appear: Malisio persona de Dunblane’ and ‘Beano magistro de Dunblane’ (Reg. Cambuskenneth, no. 122 and p. 363). A cathedral chapter was established in the 1230s, and after this the Culdees no longer appear in documents. Mention of the poverty of the diocese of Dunblane can be found about 1230 in a charter of Bishop Osbert. Following this, in about 1239, Clement, bishop of Dunblane appealed to the Pope about the wretched condition of the church at Dunblane. In a letter to the pope from William, bishop of Glasgow, and Galfrid, bishop of Dunkeld, (dated 1239), they confirmed the destitution of Dunblane’s church and the dire episcopal revenues (Reg. Cambuskenneth, no. 125). They also stated that the church of Dunblane had formerly been vacant for nearly 100 years and that nearly all of its property had been seized by secular persons. According to the letter, the pope appointed the bishops of St Andrews, Brechin and Dunkeld to provide for the church, and the two Scottish bishops suggested that the episcopal seat be transferred to the abbey of regular canons of St John in the diocese of Dunblane (i.e. the Abbey of Inchaffray). The move of the centre of the see to Inchaffray was never undertaken, but it appears that under Clement the cathedral church at Dunblane began to be rebuilt. The surviving structure is largely 13th century, though some further work on the cathedral church occurred during the 15th and early 16th centuries. The see of Dunblane had a close relationship with the earls of Strathearn, the first mentioned in records being Malise I, who fought with King David I at the Battle of the Standard in 1138. Malise was still active in 1141, but it is not known when he died. Ferteth succeeded as Earl of Strathearn, followed by Gilbert (1171-1223).

The most commonly suggested date for Dunblane’s tower is about 1150, but other dates have been proposed. Mackenzie (1845) suggested about 1140, while Fawcett, Gifford and Walker all give it a 2nd quarter of the 12th century date. Historic Environment Scotland gives a post-1150 date. Whatever the exact starting date, it appears highly likely that the tower was built in either the 2nd or the 3rd quarter of the 12th century.

Within the diocese of Dunblane, the 12th-century tower of Dunblane has strong similarities with the towers at Muthill and Dunning. Elsewhere in Scotland, the W tower of Markinch (Fife) also shows similarities.

The history of church buildings under the Culdees is enigmatic. Free-standing towers, along with raised entrance doorways are found a bit earlier in Scotland at nearby Brechin and Abernethy, both of which were also Culdee sites. The possible move of the cathedral to the abbey church of Inchaffray is of some interest in this respect. The complaint that the cathedral church at Dunblane had fallen into ruin and had been controlled by seculars for a hundred years seems to refer to the Culdees there. By moving the cathedral to Inchaffray, it would have been served by Augustinians. It can be no coincidence that the Culdees of Dunblane fall out of the records at precisely this time. The Abbey of Inchaffray had been founded by Gilbert, Earl of Strathearn, and was chosen by Jonathon (d. 1210), bishop of Dunblane, as his place of burial. The Abbey of Inchaffray was also the chosen place of sepulchre for the Earls of Strathearn.

The four voussoirs carved with chevron compare favourable with chevron voussoirs on the N nave doorway and W doorway of Dunfermline Abbey Church, which in turn show strong similarites with chevon used on the N, S and W doorways of the western end of the nave of Durham Cathedral.