Walliser roggenbrot is a Swiss rye bread produced in the Valais region. The rustic loaf with a dense crumb must contain at least 90% whole rye flour, and it is typically made with a sourdough starter. The bread keeps for a long time, and traditionally, it used to be baked in village ovens which were fired only a few times per year, so it was quite important that the bread lasted for a few months.