The renowned Festningen section in the outer part of Isfjorden, western Spitsbergen, offers a c. 7 km long nearly continuous stratigraphic section of Lower Carboniferous to Cenozoic strata. Tectonic deformation associated with the Paleogene West-Spitsbergen-Fold-and-Thrust belt tilted the strata to near-vertical, allowing easy access to the section along the shoreline. The Festningen section is a regionally important stratigraphic reference profile, and thus a key locality for any geologist visiting Svalbard. The lithology variations, dinosaur footprints, as well as the many fossil groups, record more than 300 million years of continental drift, climate change, and sea level variations. As such, the Festningen section is the only protected geotope in Svalbard, covering an area of c. 17 km2. The first detailed geological cross-section of the Festningen profile was published by Hoel & Orvin (1937), while a revised open-access field guide was compiled by Mørk & Grundvåg (2020). Read the initial publication at: https://foreninger.uio.no/ngf/VK2021/T13/Senger_etal.htm