We cannot complete this trip without visiting the national park at Þingvellir. In the years of commonwealth, from 930 to 1262, the chieftains and their followers rode to Alþingi in Þingvellir to settle their debates, on Lögberg, a natural pedestal made of lava, where the law speaker used the walls of Almannagjá gore to echo his words to the congregation.From the viewing platform here at Hakið, you can easily see all the geological events we have talked about on the way, and you have seen from a distance on our hike and standing by the lake. We can see the western edge of the rift, and the valley which has formed between the two plates as they spread apart on their evenly steady pace every year.The Þingvellir graben is surrounded by volcanoes belonging to four active volcanic systems, the Prestahnúkur and Hrafnabjörg systems in the north, and the area we were in earlier today, the Hengill and Hróðmundartindur systems in the south.Directly here north of us is Ármannsfell mountain, which was formed by a subglacial eruption which managed to break through the Weichselian glacier, forming a table mountain, strongly composed of olivine phyric basalt. As  you can see, Ármannsfell is strongly faulted.Next in line is the perfectly constructed volcano Skjaldbreiður which I mentioned to you in our last stop. Here you can easily see how huge it is, and how it  dominates the horizon to the north of the Þingvellir graben. Apart from filling the northern part of the graben here, the eruption caused a number of lava flows to enter the southern reaches of the graben and partly overflowing the somewhat older Thingvellir lava. Skjaldbreiður is the prototype of Icelandic shield volcanoes, due to its regularity. The volume of Skjaldbreiður has been calculated to be about 17 km³, and the lava covers an area of about 200 km².One of Iceland’s naturalists and poet (1807-1845), penned a poem to Skjaldbreiður after riding around it in the July 1841. I found a translated version of it, by Dick Ringler;