The building has a roofless chancel, with a triple window in the E gable. The sacristy, N of the chancel, is also roofless although the nave is still in use. The nave has traces of pointed arches suggesting the original presence of side aisles (Harbison, 1996). There is an internal staircase in the W gable, which may date partly from the early 13thc. building. The stepped gable with a short pyramidal tower is a later construction, incorporating reused Romanesque capitals at the corners. A number of stone crosses are situated in the chancel, graveyard and a field W of the church.

The church is said to have been founded by St Fachnan, possibly identifiable with St Fachtnan who founded the church of Ross Carbery (Cork) in the 6thc. The place name, derived from St Fionnabrach's Church or the Church of the White Meadow, is first mentioned in historical sources in 1055, when its stone church was burned (AI). A bishopric was established in 1152 at the synod of Kells (Gwynn and Hadcock, 1970, 83-84). The boundaries of the diocese corresponded with the territory of the Corcu Modruad, which may already have formed an administrative unit in ecclesiastical affairs (de Paor, 1955/56, 62). Little is known about the organisation of the diocese or the identity of the bishops in the 12thc. An unnamed bishop of Kilfenora did fealty to Henry II in 1172, and the 13thc. bishops are known only by their Christian name (Harbison, 1996). The see was united to Limerick in 1606-7, to Tuam in 1617-42, to Clonfert in 1742-52, and to Killaloe in 1752 (Swinfen).

The original structure of the nave and chancel appears to date from the early 13thc. The scalloped capitals and font could date from the late 12th or early 13thc., but the design of the E window clearly belongs to the 'School of the West' which flourished in the first third of the 13thc. (Leask, 1966, 54).

The presence of six or seven high crosses is the largest known number from any site in Ireland and implies that Kilfenora was the centre of a major workshop in the production of stone crosses. The limited use of figurative scenes, consisting principally of the crucified Christ and a standing ecclesiastic, is characteristic of other Irish high crosses of the 11th and 12thc. (Cashel, Dysert O'Dea, Glendalough, Roscrea, Tuam). The use of local limestone and the limited repertoire of geometric ornament, fretwork and interlace patterns is related to a group of crosses in Clare and Aran which have been dated to the late 11th and first half of the 12thc. and appear to be the product of a single workshop (de Paor, 1955/6; Cronin, 1998). The zoomorphic interlace on the Doorty cross, with Ringerike and Irish Urnes elements, is related to that on the Killeany cross (Inishmore, Galway) which is generally dated late 11th or early 12thc. and considered to be an early product of the workshop. The cross of Cathasach at Inishcaltra has an inscription suggesting a late 11th or early 12thc. date. The Kilfenora crosses also share some features with the cross shaft in Tuam cathedral, dated by inscription to 1126-52. The erection of a series of high crosses at Kilfenora in the late 11th and early 12thc. was probably connected with the Church reform movement, although it appears to have pre-dated the establishment of a diocese at Kilfenora.

The iconography of the Doorty cross is difficult to interpret. Three different types of crozier are depicted; the drop-headed form is commonly found in Irish reliquary croziers, but only one Irish Tau crozier has survived (from Co. Kilkenny, now in Dublin, NMI). Both Tau and drop-headed croziers are depicted on the base of the Dysert O'Dea cross, and there are images of Tau croziers at Killinaboy (Clare) (one is now in Corofin Heritage Centre). Harbison (2000) has suggested a reference to a hypothetical crozier reliquary. Spiral or volute croziers appear on other late Irish high crosses (including nearby Dysert O'Dea) and may be connected with the 12thc. reform movement and the idea of episcopal authority. The image of clerics ramming a bird with a crozier is similar to a scene on the cross of Muiredach at Monasterboice, possibly representing St. Paul and St Anthony (Harbison, 1981). The horseman and gabled roof also occur on Muiredach's cross, and may represent an Apocalyptic image (de Paor, 1955/6; Cronin, 1998). (Most descriptions of the Doorty cross have interpreted the image below the two ecclesiastics on the E face as a bird; however, Harbison (1992) recently interpreted it as a winged beast).

O'Farrell (1984) suggested that the unworked gable-like feature on the cross-shaft of the W cross may have been concealed by a stone house-shaped reliquary. He suggests that the shingled roof depicted at the base of the W face of the Doorty cross may be another reference to a house-shaped shrine.

Another small cross fragment (found in the graveyard in 1955 and formerly displayed in the cathedral chancel, but now lost) was decorated with a panel of fretwork and probably interlace (de Paor, 1955-6, 59; Harbison, 1992, 116, #138). It could have come from the same cross as the larger fragment in the chancel.

A further cross from Kilfenora was moved in the 18thc. to Clarisford and in 1820 to Killaloe, where it is displayed in the cathedral.