SC3177 8023. The roofless medieval chapel of St Trinian stands in a field at the foot of Greeba Hill just to the north of the A1 Douglas to Peel road about three-quarters of a mile west of Crosby in the parish of Marown. Originally dedicated to the 4th century Scottish saint, Ninian, but later the name changed to Trinian. The 14th century chapel stands on the site of a Keeill – an ancient manx name for chapel – indeed the site is also called Keeill Brisht meaning “broken church”.

It seems that an ancient burial ground and a chapel stood here from the 6th-10th century, but then sometime between 1200-1230 a medieval chapel was established on the raised circular site as a dependancy of the priory of St Ninian at Wigtown, Galloway, Scotland, but that building fell down so another chapel had to be constructed. However, according to local legend, a buggane (evil giant or goblin of manx folklore) kept blowing the roof off and so eventually the chapel was left alone without any roof – just as it is today.

The roofless chapel measures 73 feet by 19 feet with the gable (belltower) some 21 foot in height; the walls are 2-3 feet thick. The nave and chancel survive as does the gable-ended belltower and a rather broken altar. Some of the capitals show ugly carved human heads. Inside the ruin there are a number of incised stone-slabs from the 10th-11th century. One has a thin cross within a circle, perhaps a grave-slab, another has a rather worn cross on it, while a third stone has what is probably a runic inscription on its face.