The Beihai Weizhou Volcano National Geopark covers the volcanic landscape of Weizhou's northern and western coastline, where basalt formations shaped by eruptions over the past hundred thousand years give the island its distinctive character. The geology here is southern China's only active Holocene volcanic field, and the lava flows, crater remnants, and coastal cliff faces of columnar basalt read clearly once you understand what you are looking at.
The most impressive formations are along the north coast between Heping Port and the old lighthouse, where the columnar basalt meets the sea in stacked geometric columns undercut by wave action. The interior of the island still shows lava tube depressions and the slightly corrugated surface of old flow fields now covered with farms and gardens. The geopark itself is not heavily developed — there are information boards at the main viewpoints but no entrance booths or cable cars, which suits the scale of the place. A motorcycle taxi circuit of the key geological sites takes about two hours.