ST. JOHNSBURY: Anne Pace has been hearing about Dog Mountain for years, but until earlier this month, had never made a trip to the park. “I really wanted to see this place,” she said, during a visit to the grounds with her one-year-old border collie, Tam. “I put a note up for my previous border collie. He was my best buddy.” Set on 150 acres tucked away on a hillside in St. Johnsbury, Vermont, Dog Mountain has become a destination for dog lovers looking to explore nature, take in art, or pay tribute to a pet.