The site of an early medieval chapel or keeill and its associated burial ground, which are thought to date to the period AD500 to AD1000.  No surface trace of any building or enclosure now remains. Trenches dug here found no walls but traces of a burial were found in one place at a depth of 1.2 metres.


Two fragments of granite quern-stones have been found here as well as two boulders with incised linear crosses (Manx Cross No 13 and Manx Cross No 16) which are now kept in Jurby church, with casts kept in the Manx Museum. They are pre-Viking in date.


Cropmarks showing the site of the keeill, an associated trackway and field systems at Cronk Mwyllin were seen on air photographs taken by Prof G.B.D. Jones (Manchester University) in 1980-81. A detailed plan of the site using computer-graphics was also made (see illustrations card). The keeill is clearly visible, linked directly to a ditched lane, evidently leading west towards Jurby, and small enclosures and apparently settlement 'tofts' leading off from it. 


The site also has evidence of a prehistoric funerary activity. Closely adjacent to the keeill site are the traces of ring ditches, suggestive of a much earlier burial site.