The big draw near Phetchaburi is Kaeng Krachan National Park, Thailand's largest at 2,915 square kilometres, stretching west to the Burmese border. The park is about an hour's drive from town and shelters over 450 bird species, including hornbills and the black drongo, plus elephants, tapirs, gibbons, and spectacled langurs. Trails are only lightly marked in places, and a guide is worth hiring for anything beyond the well-trodden routes near the visitor centre.
To the south, the beach towns of Cha-am and Hua Hin are both within easy reach for a day at the coast.