Boundaries are important and in an age before maps, they had to be carefully marked to be remembered.
Lambeth's parish boundaries were regularly checked by 'beating the bounds'.
Now Lambeth's archivists re-enact this ancient ceremony online with a two-part, 23 mile digital perambulation.
In part one Len Reilly walks south from the Thames at Broad Wall along the boundary with Southwark to the ancient marker at Vicars Oak, now Crystal Palace.
This event is hosted by Lambeth Archives as part of the Lambeth Heritage Festival.
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