Petrified forest, Khorixas, National monument in Kunene Region, Namibia

The Petrified Forest, 42 km west of Khorixas on the C39, is a geological site where fallen tree trunks were fossilised by silicification. The largest trunks reach about 30 m in length and up to 6 m in girth, and the longest still measures nearly 1 m across at its upper end. The trunks lie broken into many pieces on sandstone that is eroding away, and welwitschia plants grow between them.

This site preserves tree remains from the Permian period roughly 280 million years ago, when ancient floods swept these plants from their original locations. The mineralization process occurred as the trunks lay buried beneath sediment over millions of years.

The site lies in the former Damaraland, and visits are only permitted with a guide, who points out the jasper trunks and the welwitschia plants growing between them. The welwitschia is Namibia's national plant, and guides explain how it survives in this dry region.

The site is reached via the C39 road west of Khorixas and features marked trails with information signs throughout. Visitors should bring sun protection and plenty of water since the grounds are completely open and exposed to the elements.

The trunks are jasper, a dense fine-grained stone, not the chalcedony or opal found at other petrified wood sites. Because the wood was replaced slowly, annual growth rings are still visible in the stone, and some trunks preserve tunnels bored by insects before fossilisation.