This chapter analyses how the close proximity to the sea and geomorphological isolation influenced the historic and architectural developments of the two settlements while they were under the administration of the Knights Templar, based on archival documentation. The establishment of the Templar Order in southern Lazio was indeed part of a bigger plan aimed at the foundation and development of the Knights Templar in Western Europe. The historical events of Santa Maria della Sorresca on Lake Paola are strictly connected to those of this Roman Templar domus. When the Annibaldi family took over from the Pironti family in 1301, they granted the possession and the rights over San Felice and Sorresca to Pietro Caetani, nephew of Pope Boniface VIII. The land estate of Sorresca remained the property of the Caetani family until 1713, when it was given to the Ruspoli family. Finally in 1789 it was given to the confraternity of Santa Maria of Sorresca in San Felice Circeo.