In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Porthleven like this:
PORTHLEVEN, a village and a chapelry in Sithney parish, Cornwall. The village stands on Mounts bay, 2½ miles W S W of Helston, and 8½ S by E of Gwinear-Road r. station; is a prosperous small sea-port; and has a post-office under Helston. A harbour was constructed hereat great cost; but cannot be entered, without difficulty, in tempestuous weather. ...
The chapelry was constituted in 1844. Pop., 1, 259. Houses, 238. The shore is rugged, and shows some curious intersections of slate rocksby trap dikes. The living is a p. curacy in the diocese of Exeter. Value, £140. Patron, the Vicar of Sithney. The church was built in 1841.
GB Historical GIS / University of Portsmouth, History of Porthleven, in Kerrier and Cornwall | Map and description, A Vision of Britain through Time.
Date accessed: 30th April 2017
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