After the German occupation and the establishment of the collaborationist Italian Social Republic, the municipality of San Marcello Piteglio was involved in extensive partisan activity. This developed especially during the spring and summer of 1944 in the mountainous area and at the Società Metallurgica Italiana in Campo Tizzoro. This important factory employed thousands of people and was directly under German control. 

Various partisan groups operated in the area, contributing to the liberation from Nazi-Fascism. These included: ‘SAP (Squadre di Azione Patriottica) Montagna Pistoiese’, ‘Brigata Bozzi’, ‘Primo Filoni’ and ‘Costrignano’. Sabotage and guerrilla warfare were continuous and helped to delay German operations for the economic exploitation of the territory and the construction of the Gothic Line (Germand and Italian defensive line). 

Throughout the entire municipal territory, the bond between the partisans and the local population was strong. The support provided by local citizens to the resistance was essential in ensuring logistical assistance, food supplies, and all kinds of support. The hamlet of Poggio, near Maresca, served as a meeting place between local residents and the fighters for freedom, who were strengthened through the provision of food, clothing, and medicines. 

On the occasion of the 35th anniversary of the Liberation of Italy, on 25 April 1980, the municipal administration installed a sandstone memorial with a burnished iron plaque near the green area of the hamlet, in memory of the contribution and sacrifice made by the population and the partisans. Today, a large rainbow-colored bench is also located near the memorial.