So I had a go at the Times2crossword tonight (No 5477). Six down "English county" 12 letters. Probably ending in "shire" I thought quite rightly. The first bit, I thought, seems to have an "N" in it. Must be Lincolnshire. But no, that messes up my other clues. Then I had an idea. Yes, they wanted an English county beginning with "D" - but not Derbyshire or Durham. Denbighshire!
*Reference to an infamous entry in the late 19th century in the Encyclopaedia Britannica index.