In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Glenwhett like this:
GLENWHETT, a hamlet in Blenkinsop township, Haltwhistle parish, Northumberland; near the Roman wall and the Carlisle and Newcastle railway, 3½ miles W by N of Haltwhistle. It is separated by Tippal rivulet from Greenhead village; and it has an inn, the garden-wall of which includes a Roman altar.
The location is where the name "Glenwhett" appears on the Ordnance Survey 1:10,560 map of Northumberland of 1865, accessible on the old-maps.co.uk site. It appears to refer to the part of Greenhead east of the Tipalt Burn. Additional information about this locality is available for Greenhead
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 Glenwhett has changed, please see our redistricted information for the modern district of Tynedale. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Glenwhett and units named after it.
GB Historical GIS / University of Portsmouth, History of Glenwhett, in Tynedale and Northumberland | Map and description, A Vision of Britain through Time.
Date accessed: 11th December 2013
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