It goes by the name 'Park Chapel', though chapel is a generous word for what amounts to an 18-metre retaining wall projecting three metres from a field fence, its stones shaped more by necessity than craft. At its midpoint stands a crude altar, flanked by two pointed-arch recesses, and tucked within the wall is a tiny cavity, barely 25 centimetres wide and 30 centimetres high, constructed from quartz boulders and sealed with a stone tablet. That tablet bears an inscription: 'R C Chapel from 1772 to 1805'.

The dates place this structure squarely within the era of the Penal Laws, a body of legislation that, from the late seventeenth century onward, severely restricted Catholic worship in Ireland. Catholic clergy were barred from officiating publicly, and congregations were forced to gather outdoors or in makeshift shelters, often at sites known as Mass rocks or Mass stations. These were not permanent buildings but functional arrangements, sometimes just a flat stone in a field, sometimes, as here, a low wall against a hillside that could double as a windbreak. The small quartz-built cavity at Deerpark is thought to have functioned as a tabernacle, the place where the consecrated Eucharist would be reserved, and its stone door would have kept it concealed when not in use. By 1805, the date on the inscription, Catholic Emancipation was still decades away, but the gradual relaxation of enforcement through the late eighteenth century had begun to allow more conventional chapels to be built, which likely explains why Park Chapel fell out of use.