St Trinian's Church, Medieval church ruin in Crosby, Isle of Man

St Trinian's Church is a medieval church ruin located at the foot of Greeba Hill in Crosby. The stone walls still stand but the roof is gone, leaving open views of the interior and allowing visitors to see the carved stone elements and burial markers inside.

St Trinian's is recorded as a ruin of a 14th-century church built on an ancient site, marked by a 7th-century cross on a grave before the altar. Construction may have halted in 1343, when William Montagu, 1st Earl of Salisbury, conquered the island and expelled its Scottish owners, including the monks of Whithorn Priory, to which the church belonged.

The church displays ancient carved stone slabs with human heads and crosses that marked burial places. These carvings show how people expressed their faith through stone work at this sacred location.

The site sits along the main road from Douglas to Peel, making it easy to find and stop at. There are no entrance fees or fixed opening times, so visitors can look around whenever they pass by during daylight hours.

Local folklore tells of a Buggane, a supernatural creature from Manx mythology, who supposedly destroyed the church's roof repeatedly. This creature became part of the island's storytelling tradition and explains why the building remains open to the sky today.