During the Penal Laws era, roughly from the late seventeenth century through much of the eighteenth, Catholic worship was suppressed under a body of legislation that banned priests, outlawed Catholic education, and stripped Catholics of property and political rights. In response, congregations met outdoors at designated spots, often a flat rock serving as an altar, a hollow in the hillside offering concealment, or a particular arrangement of stones that a community quietly recognised as sacred ground. These sites are known as Mass rocks or Mass stations, and they scatter the Irish landscape in their hundreds, most of them unmarked on any conventional map.

The Troiste site is one such place, recorded as a penal Mass station but with little else currently documented in the public record. What the classification alone tells us is significant enough. Mass stations were not improvised in a moment of crisis; they were established, remembered, and returned to across generations. A community had to trust one another absolutely, post lookouts on surrounding high ground, and risk transportation or worse if a priest was caught officiating. The flat stone that served as an altar at such sites, sometimes called a Mass rock, occasionally survives in place, worn smooth or faintly incised, though many were later incorporated into field walls or simply lost to the land.