1. Mount Everest (8,848m)
2. K2 (8,611m)
3. Kangchenjunga (8,586m)

_Longest Ranges_

1. Andes (7,000km)
2. Himalayas (2,500km)
3. Rocky Mountains (4,800km)

_Oldest Mountains_

1. Appalachian Mountains (480 million yrs)
2. Scottish Highlands (3.5 billion yrs)
3. Australian Great Dividing Range (300 million yrs)

_Highest Volcanoes_

1. Mauna Kea (4,205m)
2. Ojos del Salado (6,893m)
3. Kilimanjaro (5,895m)

_Unique Features_

1. Mount Fuji's symmetrical cone
2. Grand Canyon's vast gorge
3. Swiss Alps' picturesque villages

_Challenges_

1. Climbing the Seven Summits
2. Trekking the Inca Trail
3. Conquering K2's treacherous slopes