A trip to Paris wouldn't be the same without taking a moment to gaze up at the great looming towers of the Gothic Notre Dame Cathedral with its watchful gargoyles on every corner. Today, celebrated journalist Simon Jenkins joins Dan to discuss 'humankind's greatest creation'; the cathedral. Simon has travelled across Europe- from Chartres to York, Cologne to Florence, Toledo to Moscow and Stockholm to Seville - to illuminate old stalwarts and highlight new discoveries. They compare favourites and share which ones they think are overrated. Simon's new book is called 'Europe's 100 Best Cathedrals'.