Clay banks (linear mounds of earth created in the past by man-power alone) inland from coastal lowlands obviously had a different function to flood defence clay banks. One such function was to define parish boundaries. Since a Papal diktat of the early Middle Ages had required people to attend their local church only (this to ensure that church income in a given area could be maintained) the definition of the parish boundary was of particular importance to the rector and incumbent of the local church, this defining which people were committed to which church. Later, civil reforms, particularly of the Tudor Age, imposed secular local government responsibilities on the unit of the parish, albeit through the medium of the ‘vestry’, this resulting in some crossover between secular and ecclesiastical responsibilities within parish boundaries. By the time that parish boundaries and parish councils as we know them today were created in late Victorian times Ordnance Survey maps and greater flexibility over persons places of worship had made physical, on the ground, evidence of parish boundaries unnecessary. However, despite weathering and the impact of modern agriculture, some remnant clay bank parish boundaries remain – see above, a section of the parish boundary between the parishes of Barton on Humber and Horkstow. Horkstow is one of the ‘Low Villages’ of North Lincolnshire, for a study of their historical geography and further discussion of parish boundaries see the relevant article in the Publications section.
The remnant clay bank shown above is particularly interesting as beside it is a public footpath. This is not unusual as modern public rights of way, secured in law, are often the formalisation of ancient footpaths recognised in local custom. In past times parish boundaries would have been accompanied by such a path as annually the church incumbent would lead a walk around the parish boundary to re-establish its delineation. In local custom this event often took place at Rogation-tide, this, a springtime celebration in the Christian calendar, coinciding with Ascension-tide, that being, according to the story in the Christian Bible, the time when Jesus of Nazareth ascended to Heaven, 40 days after His resurrection.