In 1887, John Bartholomew's Gazetteer of the British Isles described Ynysddu like this:
Ynysddu, ry. sta., Monmouthshire, 4 miles NW. of Risca and 2 miles S. of Tredegar Junction.
Additional information about this locality is available for Mynyddislwyn
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 Ynysddu has changed, please see our redistricted information for the modern district of Caerphilly. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Ynysddu and units named after it.
GB Historical GIS / University of Portsmouth, History of Ynysddu, in Caerphilly and Monmouthshire | Map and description, A Vision of Britain through Time.
Date accessed: 12th December 2013
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