A small rectangular church (c. 11 m. x 7.3 m.) with a plain W doorway and reconstructed Romanesque windows in E gable and S wall. There is a stone bench along the nave wall inside the W wall and part of the S wall. The E end is raised by a step and has a stone altar. Two stone crosses are set into the exterior of the E wall and a group of crosses stands near the E end. There is a plain shaft standing to the W of the church.

The monastery was built by St Abban, and named after St Mobecoc or Becan, (d.689).

The Romanesque fragments were found in the collapsed stonework of the walls and were re-erected with them. Leask's drawing, (1955, fig.58), is inaccurate in showing the chevrons of the E window as regular. Waddell and Holland (1990) suggest that the finial which is now on the S window comes from the E window, but there is no evidence for this. They illustrate and record a number of other fragments: two jambstones with chevron ornament (possibly from another window) and a small scallop capital. Gabled windows are found at a number of other sites in Ireland: at Killeshin (Laois) with a plain gabled frame; and at Inchicronan and Kilcorney (Clare) with a decorated gabled arch.