Klamath Mountains animal species, including black bears, large cats, owls, eagles, and several species of Pacific salmon. Millions of acres in the mountains are managed by the United States Forest Service. The northernmost and largest sub-range of the Klamath Mountains are the Siskiyou Mountains. Physiographically, the Klamath Mountains include the Siskiyou Mountains, the Marble Mountains, the Scott Mountains, the Trinity Mountains, the Trinity Alps, the Salmon Mountains, and the northern Yolla-Bolly Mountains. They are a section of the larger Pacific Border province, which in turn is part of the Pacific Mountain System (Pacific Coast Ranges) physiographic division. These are the ten highest
Black Mountains, Wales suggestion too that the names Hatterrall Hill and Mynydd y Gader may also once have been used to apply to the entire range of the Black Mountains though the former later became confined to the vicinity of its eastern ridge. The latter is now recognised in Pen y Gader-fawr (Pen y Gadair Fawr) and Gader Fawr (Gadair Fawr); names applied to the hill at SO 229288. Cadair, mutated to 'gadair' and anglicised as 'gader', means 'seat' or 'chair' in Welsh. The highest mountain in the group is Waun Fach whose heavily eroded peat summit plateau attains a height of .