In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Portsdown like this:
PORTSDOWN, a hill and a hundred in the S E of Hants. The hill extends from the neighbourhood of Havant, 6 miles westward, to the neighbourhood of Fareham; culminates at an altitude of 447 feet; flanks allthe N side of Portsmouth harbour; commands a magnificent view to the E, the S, and the W; is crowned, at itshighest point, by a lofty obeliskal pillar, to the memory of Nelson, and serving as a land-mark to mariners approaching Spithead; consists of chalk rocks; has fortifications, constructed in 1865 and following years, addinglargely and very materially to the defences of Portsmonth and Gosport; and, at the Running Walk near Widley, has a great fair on 26, 27 and 28 July. The hundred contains Bedhampton parish, and eight other parishes; and is in Fareham division. Acres, 21, 943. Pop. in 1851, 4, 547. Houses, 888.
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 Portsdown has changed, please see our redistricted information for the modern district of Portsmouth. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Portsdown and units named after it.
GB Historical GIS / University of Portsmouth, History of Portsdown, in Portsmouth and Hampshire | Map and description, A Vision of Britain through Time.
Date accessed: 22nd May 2013
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