Derek is back with eight more incredible walks around Wales. In this edition, he is on ranger duties at a country estate in Carmarthenshire, exploring Dinefwr Park's 800 acres of magical medieval landscape and getting close to a very rare cattle breed. In the Vale of Glamorgan, Derek is joined by Olympian Colin Jackson. Together they explore a five-mile coastal route that has it all - dinosaur footprints, WWII gun battery remains, the site of a major communication breakthrough and an iconic Victorian pier.