The Qixing Mountain (七星山, literally "Seven Star Mountain") is located on the Datun Volcano Group and is the highest mountain at the rim of Taipei City and Taipei Basin. It is also the highest (dormant) volcano in Taiwan. It located in the center of Yangmingshan National Park and its main peak is 1,120 metres (3,675 ft) above sea level.
It began erupting about 700,000 years ago. There was a crater at the peak but it became seven small peaks due to post-eruption erosion.
The mountain has faults running across the southeast and northwest contours with volcanic landforms like hot springs and fumaroles.