At heart of the middle Somme valley, Tirancourt marshes cover an area belonging to 3 villages: La Chaussée-Tirancourt, Ailly-sur-Somme and Breilly. Bordered by the Samara site and river Somme to the south, this natural setting, wild and protected, is home to a great variety of habitats and several species of plant and wildlife typical of alkaline peat bogs - species that are often rare and threatened. Among the most symbolic species to be found in this marsh is Greater Spearwort, a protected buttercup standing over 1 metre high and growing in great numbers here. During your walk, keep your eyes peeled for Fjord horses and Nantais cows who graze this site for part of the year.