Almannagjá, (“Public ravine”) in ancient times many of those attending the Alþing camped on the level grassy bottom of the ravine. Almannagjá is the largest and most famous tectonic fissure in the Þingvellir National Park. Its western edge is higher than the eastern one which is considerably lower. The entire piece of land between Almannagjá and Hrafnagjá is a graben (fault trough). View-dial on the edge of Almannagjá.
Hakið, the interpretive centre is at the top of Almannagjá. There visitors can discover the history and nature of the area with the help of a multimedia program. The history and nature of Þingvellir is described in detail on large screens where diverse and interesting photographs and drawings may be viewed.