Countryfile is in the county of Northamptonshire. Matt Baker is exploring a section of the Grand Union Canal and finding out about the huge amount of work that goes into keeping it ship-shape for the thousands of visitors who come every year. Julia Bradbury is discovering some of the hidden heritage of the county. Her first stop is Rushton Triangular Lodge - a folly built by a Catholic in the 16th century. She then travels to Canons Ashby - another house full of symbolism but this time it's the illuminati at work. Julia will also be visiting a farm on the site of a scheduled listen monument where the farmers have a unique take on diversification. They make gin from the spring water that flows through the land and claim to be the only artisan gin makers in Northants. Britain's deer population is booming and these days, if you are lucky, you can even spot them on the fringes of some of our largest cities. But in many parts of the country these beautiful animals are now seen as a pest that destroys our natural environment and brings danger and disease to humans. So, is it time for drastic action? Tom Heap finds out. Adam Henson is heading back to Cheshire to collect his wild Exmoor ponies. They've been in training for few weeks now - but will they be tame enough for him to handle?