Skaftafell strata display well the frequent shifts between glacial and inter-glacial conditions. Tho oldest tillite in the area is about 4 million years old. The Skaftafell vicinity has experienced considerable volcanic activity, with the 1362 Öræfajökull eruption producing the most ash of any Icelandic volcano since the settlement and another, smaller Öræfajökull eruption occurring in 1727. As shown once again in 2011, the subglacial volcano Grímsvötn is the country's most active volcano, and is also famous for the huge jökulhlaups or glacial floods that originate from it. Plants and wildlife Compared to many south coast areas, Skaftafell has a mild, pleasant climate, often benefiting from the towering shelter of Öræfajökull. Birch trees and occasional rowans cover the rich undergrowth of the lower slopes and the birch trees in Bæjarstaðarskógur grow higher than most other native birch. Several flowering plants distinctive to East Iceland are common here: the harebell, yellow saxifrage, and pyramidal saxifrage. Since sheep stopped grazing at Skaftafell, the vegetation has undergone great changes and is quickly making inroads on the glacial deposits in front of Skaftafellsjökull and in Morsárdalur valley. Species such as garden angelica, wild angelica, sea pea and arctic river beauty, are hardly ever found on grazing land, but have now become common. Birch and willows are also starting to colonise land. Down in the Skaftafell woods, the redwing, redpoll, and wren are common, while the snipe, ptarmigan, golden plover, and meadow pipit, appear more frequently higher up the slopes. Other birds seen frequently include the raven, merlin, wheatear, and snow bunting. Although the sole wild mammals are the Arctic fox, mink and field mouse, the local insect fauna is considered quite diverse compared to most of Iceland. National park and tourism When Vatnajökull National Park was founded in the summer of 2008, the former Skaftafell National Park became part of it. Skaftafell has been protected since 1967, with the aim of opening it up to the public while also conserving its flora and fauna, landscape and cultural remains. Open all year, the Skaftafell Visitor Centre serves the Southern Territory of Vatnajökull National Park and provides information on the park and its environs, trails, nature and history, as well as on other recreation and services. Display boards at the Centre describe the intertwined history of people and nature at Skaftafell. Skaftafell has a selection of hiking trails, and the spacious campground has facilities for tents, folding