Google’s 3D Warehouse allows you to search through 3D models of various kinds of collections and models that people have sketched. You can find all kinds of medieval related items: castles, buildings, cathedrals, weapons, etc. You can search in broad terms (e.g. – medieval castles), or more specifically, such as Notre Dame Cathedral. The warehouse is also integrated with Google maps, so for example with Notre Dame Cathedral, you can select the Map or Street View tabs to zoom in on the actually location of the building.