Around 1801, Francisco Terrés i Serra designed and developed a sustainable wave-powered flour mill in Vilanova i la Geltrú, a town located on the Mediterranean coast south of Barcelona, Spain. The mill, which was located on the seashore, consisted of a system of paddles driven by waves that provided the energy necessary to pump sea water to a a gathering pond located at a height of five metres above sea level. This water was then fed to a wooden waterwheel that, via a lantern wheel, turned two sets of millstones in the upper room of the mill where the flour was ground. The mill is now located more than 50 metres from the water line due to the sedimentation of the coastline caused by the construction of nearby breakwater walls. Only a small part of the building is still standing, however, and there are no traces of the original hydropower or pumping systems. Using information gathered by the historian Francisco Conde and original plans of the mill obtained from the Navy Command in Barcelona, we created a virtual reconstruction of the flour mill complex and its hydraulic components and a 3D simulation of how the mill operated.