The reported site of a Mesolithic settlement at Glen Wyllin, where F. Swinnerton carried out an excavation in 1889. 


The Glen Wyllan site was found by Canon Quine who called for the aid of Swinnerton who had discovered a similar industry in the South of the island at Port St Mary. The site was situated just behind Kirk Michael village, in an area of high scrub land, sloping down in all directions. The 'excavations' by Swinnerton revealed several thousands of flints, but only a small proportion now survive in the Manx Museum and some in the British Museum. A series of saucer-shaped pits containing 'burnt twigs' and flints were also discovered, which Clark interpreted as hut foundations but were almost certainly hearths similar to those found at Mount Sandel, Northern Ireland. 


The Glen Wyllan site was discovered in the field numbered 931 on the 1869 1:2500 scale Ordnance Survey map and is thought to continue into the adjacent field to the north (number 884) at  Ballacregga, discovered by C.H. Cowley in 1909, in the area of SC 318897 on the lip of the steep-sided Cooill Darry valley. A large collection of the flints from this area are in the Manx Museum.


Further excavation undertaken close to the Swinnerton excavations in 2000 found over 1000 struck Mesolithic flints as well as charcoal and charred hazelnut shells. Radiocarbon dates from the shells dated this settlement to approximately 7,000BC, making this the earliest known settlement site on the Isle of Man.