Derek turns Pied Piper as he launches a walk of 800 children marking the anniversary of ‘People Power’ that saved a stretch of the Loughor Estuary for families to enjoy.On this Carmarthenshire coastal walk from Pwll to Kidwelly, the weatherman also discovers a former munitions factory that employed 6,000 people, has a spin in a racing car and learns the story of Wales’s feisty warrior princess Gwenllian.