"Near Edgecoombe, about forty miles up channel"

As Manderley is located around Menabilly near Fowey on the south Cornish coast (see bookmark p.1), we can assume that 'forty miles up channel' means 40 miles to the east of Fowey, and that the 'channel' is the English Channel.

Edgecoombe may be based on the ancient manor house known as Edgecombe Manor in the village of Milton Abbot in Devon, located between Launceston and Tavistock.

There is also a coastal town called Salcombe in the district of Devon, about 65 miles from Fowey by road.

 

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