The site of an early medieval keeill or chapel which is thought to have been in use between circa AD500 and AD1000.  The site of the keeill is situated on the crest of the hill facing south at about 75 metres above sea-level. The keeill enclosure is shown on the 1870 1:2500 Ordnance Survey map and measures about 30 metres in diameter. 


Some years ago the last remains of the walls were removed by the owner Mr T. Corlett. An entry in the Ordnance Survey Object Name Book (1869-72 - destroyed in 1940) refers to Keeill Tushtagh as being: 'On an eminence of farm of the same name formerly stood an ancient Treen Chapel. In cultivating it a few years ago, the remains of a small building composed of earth and stones was removed. The site is still traceable, and the track of the fence which surrounded the same is still strongly marked, within which the graves have been found. The name is widely known, and signifies the Church of Wisdom or Knowledge. Tushagh-sensible or intelligent.'  The authorities given for Keeill Tushagh are Mr John Corlett, John James Sayle (Smeale Beg), and J.T. Martin, Esq., C.P., M.H.K. (Smeale). 


Kermode lists the 'sites of Keeill Tushtag' but also refers to 'Cronk y Cat, Smeale beg, over quarter mile SE of Keeilltushtag house; there seems to have been a small Fort here. On a natural rounded hill with level platform on the top, Mr Sayle remembers a low circular mound of earth and boulders removed in his boyhood'. The similarity of siting and references to Messrs Corlett and Sayle would make it possible that Cronk y Cat 'fort' is the same as Keeill Tushtag.