The Sigiriya Rock is the remains of a hardened magma plug from a long-eroded volcano. The summit is nearly 200 meters above the surrounding plain and 370 meters above sea level. It was formed over two billion years ago when the area around Sigiriya was rife with active volcanoes. Hot molten lava from the earth’s inner core spewed out onto the surface forming numerous mountains of varying size.
Over the ensuring years the volcanic active ceased. Natural erosion by wind and rain slowly eroded the outer surface of the volcano exposing its solidified magma core. The 200 meter exposed lava plug is only the tip of a solidified lava shaft which extends deep into the earth’s surface.
The numerous scattered granite boulders around Sigiriya are the remnants of the lava that once flowed from this volcano.
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