Agust Gudmundsson was a volcanologist at the Nordic Volcanological Institute, University of Iceland, for many years, before being appointed to the Chair of Hydrogeology of Solid Rocks at the University of Bergen (Norway) and subsequently the Chair of Structural Geology and Geodynamics at the University of Goettingen (Germany). A leading volcanologist and structural geologist, as well as being editor of many earth-science journals and a member of the European Academy (Academia Europaea), Gudmundsson holds a University of London Chair of Structural Geology at Royal Holloway (United Kingdom). Gudmundsson has been a guide on many geological excursions in Iceland, both for geoscientists as well as for general visitors, including all those described in the book.