the park's dominant natural features include the highest peak in the maritimes, mount carleton, and several large freshwater lakes (nictau lake, little nictau lake, bathurst lake, and the nepisiguit lakes). located at the headwaters of the nepisiguit river and the tobique river, the lakes offered a convenient portage route between the nepisiguit and saint john river watersheds. the canadian portion of the international appalachian trail passes through the park.