Stretching 15 miles down the river valley from Matlock Bath to Derby, the World Heritage Site contains a fascinating series of historic mill complexes, including some of the world's first 'modern' factories.
Danielle Barker, who runs a jewellery shop in Matlock, said traders had noticed a drop in business after a supermarket was built on land that was used as a free car park.
"Car parking charges in Matlock are on par with the big shopping centres where there is more choice and bigger stores rather than independent businesses so people will often go there instead, " Ms Barker said.