Whimberries (or wimberries, or billberries, bilberry, whortleberry or winberry) are small dark mauve berries from a low-growing shrub of the genus Vaccinium, which grow in abundance in parts of the Pennines. They are commonly collected locally but only rarely available commercially. It is unclear whether they are more closely related to the North American 'Blueberry' or the European 'Myrtle', but the taste and appearance is very similar.

Wimberry pie made in Glossop
Image: Chrissi Nerantzi https://www.flickr.com/photos/chrissinerantzi/

Heather and Whimberry in the Pennines
See: Whimberry Relish