maps2                   A list with 8 'ggplot2' objects of swiss
                        territory boundaries, at various levels.
maps2_                  Prepares the base of a map, starting from a
                        data frame with longitude (long) and latitude
                        (lat) coordinates, as a 'ggplot2' object
shp_df                  A list with 8 data frames of swiss territory
                        boundaries, at various levels.
shp_sf                  A list with 8 'sf' objects of swiss territory
                        boundaries, at various levels.
theme_white_f           theme_white_f is a 'ggplot2' theme function
                        that can be added to a 'ggplot2' object to
                        eliminate axes, ticks and put white background
