It can now be found in Rothe House in Kilkenny, having long outlasted the family whose ambitions it once announced. The castle itself, on a spur of high ground above the Kings River, is a more complicated survival: a multi-period complex consisting of a fortified house, a bawn (a walled enclosure, typically defensive, surrounding a tower or house), and a substantial mural tower, with an external moat still traceable around much of the site.

The story of Castle Eve is, in large part, the story of a single unlucky military adventure and its long consequences. The site originated as the stronghold of the D'Erley family, recorded in the Red Book of Ossory around 1300 and 1320 as 'Curia de Erleyestoun' and 'Castrum Erleye'. In 1367, John D'Erley joined the campaign of Edward, the Black Prince, in Spain, where he was taken prisoner. The ransom demanded for his release was so ruinous that the family were forced to sell the Manor of Earleston entirely, and by the end of the fourteenth century the Sweetmans had acquired both the property and the title of Baron of Erley. They held it for nearly three centuries, accumulating sheriffdoms and pardons in roughly equal measure: James Sweetman was Sheriff of Co. Kilkenny in 1543 and received a pardon in 1549; William Sweetman, the largest freeholder in the Barony of Kells around 1560, served as sheriff again in 1564. The end came with the Confederate Wars of 1641 to 1652, after which William Sweetman's lands were confiscated and he was transplanted to Connacht in 1654. Local tradition holds that Cromwellian troops battered the castle and killed all its defenders save one, a story lent some weight by the large quantities of human bones reportedly uncovered in an adjoining field during later cultivation. The confiscated manor passed to Captain Henry Baker, who received it in settlement of military arrears amounting to £479 13s. 4d. He was elected MP for Callan in 1661 and died the following year, after which his portion was further subdivided among his children. A will dated from 'Castle Ife' in 1672 suggests that William Sweetman managed to return after the Restoration, and the property eventually passed through his daughter's marriage into the Conway family. The Conway-Sweetmans remained in the neighbourhood until around 1845, when the last of them emigrated.

The mural tower at the north-west angle of the bawn is the oldest surviving fabric on the site. Built of roughly coursed limestone rubble with a base-batter, it retains a pointed vault over the ground floor, traces of plaster rendering on its walls, and a plaster cornice moulding. A cross-loop survives in the north-west wall at ground-floor level. The internal ground level of the bawn sits some three to four metres above the external ground, which makes the tower appear considerably taller from outside than within. A photograph taken around 1900 by the local historian Rev. William Carrigan shows a pointed gable above the south-west wall that has since collapsed. The east portion of the bawn has not survived at all, and heavy ivy growth now obscures whatever features remain at first-floor level inside the tower.