Just to the east of Lesmahagow's main street, Abbeygreen, is Church Square. The far end of the square is formed by the west gable and modest spire of Lesmahagow Old Parish Church, built in 1803. If you walk round to the south side of the church, a gate in a set of railings gives access to a collection of stone foundations set within a larger grassy area. This is what remains of Lesmahagow Priory.
The remains you can see today were uncovered in an archaeological excavation in 1978. The main structure is formed by the lower several courses of stonework from the priory refectory, which stood on the south side of a cloister, or open square. You can also see the base of part of the inner wall of the east range, the buildings that would have enclosed the cloister on this side, and the bases of some of the walls of the west range. The priory church would have stood on the north side of the cloister, under the Old Parish Church, and the south and west of the site are hemmed in (and presumably lost beneath) village housing.
There is open ground to the east of the excavated area, extending towards the near bank of the River Nethan, and it is possible that there are more remains, perhaps of a chapter house and Prior's lodgings, still to be unearthed there.
It helps considerably when visiting Lesmahagow Priory if you've already visited other more complete Scottish priories and abbeys, as there is a certain commonality of layout and form that links many of them together. Even so, it takes a real feat of imagination to try to fill in the huge gaps and picture what once stood here. If you've not visited other similar buildings, then Lesmahagow Priory is a difficult place to begin to unravel. It would certainly be a bonus if the - otherwise very helpful - information board could include some sort of "as it was" depiction of the complex of buildings that once stood here.
Lesmahagow Priory was founded as a Tironensian (or reformed Benedictine) establishment in 1144, when it became a daughter-house of Kelso Abbey. The priory was jointly founded by King David I and by John, Bishop of Glasgow, who both granted estates whose incomes could support the new community. The reason for the choice of location can be found in the founding charter of the priory, which dedicated it "in reverence to God, Saint Machutus and the King's firm peace."
Saint Machutus (or Mahego or Malo) was a Welsh monk and follower of Saint Brendan, who arrived in the area in the second half of the 500s, and seems to have established a monastery here. The name "Lesmahagow" is often said to be derived from "the enclosure of St Machutus", and is the main evidence for that early monastery. There was certainly an existing church on the site when the priory was founded, and it is attractive to speculate that there may have been (and still be) an unbroken tradition of Christian worship on the site extending back to the 500s.
The "firm peace" referred to by David I was perhaps more a hope than an expectation. In 1335 the priory was attacked by English troops under John of Eltham, brother of King Edward III, and it is said that many local people taking sanctuary in the priory church were killed when it was set alight.
Monastic life at Lesmahagow Priory would have come to an abrupt halt with the Reformation of 1560. The priory buildings were acquired by the Earl of Roxburghe in 1607, and by the end of the century everything except the priory church had been quarried down to ground level for its stone. The priory church continued in use as a parish church, but by the end of the 1700s it seems that something larger was required. As a result the church that had stood here since 1144, perhaps incorporating parts of earlier structures, was sadly demolished to allow the building of the 1803 Old Parish Church that still stands on the north side of the site today.