Use the Sandstone Trail OS Map link to locate the place in the clue that caused such a quandry: "will it be seven miles southwest to the (now canalside) site of a battle where, one September 24, parliamentarians had a good day? Or a castle through which the MDF almost slices? The castle wins. I head six miles south, in so doing crossing the aforementioned canal (66½ miles long), to find the castle a tad beyond. Trace the canal above the castle in the opposite direction until you reach the battlefield that is "canalside."