Banagher Old Church, near Dungiven, is a state-care monument of the late 11th century onward. Local tradition credits its foundation to St Patrick or, more commonly, St Muiredach O'Heney. A date of 474 was etched on it in the 1730s, but Wikipedia says there is no evidence it is that old.
In the graveyard stands a seven foot high mortuary house said to hold the saint's remains, which made the site an important pilgrimage destination for centuries. Wikipedia says the presence of the relics gave rise to the still-living tradition that Banagher sand is supposed to bring good luck, especially in sporting events. Outside the church is a building called the residence, where the saint was supposed to have made his appearances.
The same saint features in the legend of the last serpent of Banagher Glen, so the two records belong together.
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