Japanese warning sign on the crater rim of Mount Naka active volcano, Mount Aso, Kyushu, Japan, Asia

Mount Warning and Tweed Valley, New South Wales, Australia, Pacific

Japanese warning sign on the Crater rim of Mount Naka, an active volcano, Mount Aso, Kyushu, Japan, Asia

Japanese warning sign on the Crater rim of Mount Naka, an active volcano, Mount Aso, Kyushu, Japan, Asia

One of Jeju Island's many lighthouses stands against Mount Sanbangsan and Mount Hallasan, a shield volcano, Jeju Island, South Korea, Asia

Japanese warning sign on the Crater rim of Mount Naka, an active volcano, Mount Aso, Kyushu, Japan, Asia

Mount Warning and Tweed Valley, New South Wales, Australia, Pacific

Grizzly warning sign, Mount Revelstoke Ranger Station, Meadows in the Sky, Revelstoke National Park, British Columbia, Canada

Sign Attention curves along the natural road, Laguna Amarga, Torres del Paine National Park, Última Esperanza Province, Chile, South America

Road Sign Attention curves at Lago Pehoe, Torres del Paine National Park, Última Esperanza Province, Chile, South America

Scenic Byway 12 in front of Capitol Reef National Park, Utah, USA, North America