Vatnajökull National Park was inscribed on the World Heritage list under natural criterion (viii). That means that the area qualifies as an outstanding example representing major stages of earth's history, including the record of life, significant on-going geological processes in the development of landforms, or significant geomorphic or physiographic features.

Unique nature

From the description:

This iconic volcanic region covers an area of over 1,400,000 ha, nearly 14% of Iceland's territory. It numbers ten central volcanoes, eight of which are subglacial. Two of these are among the most active in Iceland. The interaction between volcanoes and the rifts that underlie the Vatnajökull ice cap takes many forms, the most spectacular of which is the jökulhlaup – a sudden flood caused by the breach of the margin of a glacier during an eruption. This recurrent phenomenon has led to the emergence of unique sandur plains, river systems and rapidly evolving canyons. Volcanic areas are home to endemic groundwater fauna that has survived the Ice Age.

The coexistence and ongoing interaction of an active oceanic rift on land, a mantle plume, the atmosphere and an ice cap, which has varied in size and extent over the past 2.8 million years, make the property unique in a global context. Earth system interactions are constantly building and reshaping the property, creating remarkably diverse landscapes and a wide variety of tectonic, volcanic and glaciovolcanic features. Especially interesting and unique in this regard are the basaltic lava shields (Iceland shields), volcanic fissures and cone rows, vast flood lavas, and features of ice dominant glacio-volcanism, such as tuyas and tindar. Interestingly, the well exposed volcanic features of the property have been used as analogues for similar features on the planet Mars. Geothermal heat and subglacial eruptions produce meltwater and jökulhlaups that maintain globally unique sandur plains, to the north and south of the Vatnajökull ice cap, as well as rapidly evolving canyons. In addition, the property contains a dynamic array of glacial- and geomorphological features, created by expanding or retreating glaciers responding to changes in climate. These features can be easily accessed and explored at the snouts of Vatnajökull’s many outlet glaciers and their forelands, especially in the southern lowlands, making the property a flagship glacial research location.