In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described The Boundary like this:
BONDARY, or Barton-Road, an extra-parochial tract in the district of Ashby-de-la-Zouch and county of Derby; 2 miles N of Ashby-de-la-Zouch. Pop., 52. Houses, 9.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing The Boundary has changed, please see our redistricted information for the modern district of South Derbyshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering The Boundary and units named after it.
GB Historical GIS / University of Portsmouth, History of The Boundary in South Derbyshire | Map and description, A Vision of Britain through Time.
Date accessed: 18th December 2014
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