You may have noticed small stone or metal plaques installed on buildings which are inscribed with some letters and a date.
These are typically parish boundary markers, marking the geographical reach of a particular parish. The letters refer to the parish name and the date when the boundary was set or marked (some markers actually have more than one date, the second being when parish boundaries were confirmed).

Traditionally, parishioners were reminded of the boundaries each year at Rogationtide – the three days of the Monday, Tuesday and Wednesday before Ascension Day (39 days after Easter Sunday) – in a ceremony known as the ‘Beating the Bounds’.
This custom involved the priest and parishioners, led by the churchwardens and beadle, walking around the stones which served as boundary markers and pausing to beat each one with sticks and pray for protection and blessings (apparently there was also a practice of pushing boys from the charity schools into the boundary walls so they’d remember them or beating them with willow wands when there was no wall).
The boundary stones have, in more recent centuries, been replaced by the plaques in London but the ceremony is still carried out in some parishes.
Interestingly, in some parishes, the boundary is located in the midst of the Thames and boats are taken to ‘beat the mark’ in the middle of the river.


