Songaksan

[Jeju] Mt. Songak is a simple volcano on Jeju Island which has double craters and a parasitic volcano. Crater 1 is about 500 m in diameter, 1.7 km in circumference. Crater 2, the mouth of the volcano in Crater 1, is about 400 m in diameter, 69 m in depth and leans vertically. From Sanyisu-dong to the summit and ridge of Mt. Songak there are...
Found on http://en.wikipedia.org/wiki/Songaksan_(Jeju)
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