The study published in 2015 of an important medieval coin hoard found in the territory of the Maremma Regional Park (Tuscany – Italy) gave impulse to an archaeological survey carried out in the years 2016-2019 as part of a PhD Project. The research work led to the discovery of a previously unknown medieval settlement situated in a narrow valley south of the castle of Collecchium (Magliano in Toscana – GR). The complex consisted of a church built in Romanesque style and other annexed buildings, now completely collapsed and still showing all around unusually well preserved traces of a medieval landscape with fields suitable for cultivation, a spring, paths and even a quarry. The materials recovered during the survey shows that the church was externally enriched with architectural decorations and figurative bas-reliefs, including that of a horseman. The settlement was in use between the late 11th and 13th centuries, a period in which the interests of the San Salvatore al Monte Amiata Abbey and those of the powerful Aldobrandeschi family intertwined in this area, until the intervention of Siena with the purchase of the nearby port of Talamone in 1303. Surface survey and non-invasive methods have allowed to collect useful archaeological data and to avoid destructive intervention such as excavating in a protected natural area. The site is now included in two itineraries and is fully accessible to visitors of the Regional Park.