Part of Pelagios' first Workpackage is to decide on a Common Ontology for Place References (COPR). In doing so we are not attempting to reinvent the wheel - far from it. Good Linked Open Data practice is to reduce, reuse and recycle. To that end we have been investigating a variety of options and are now basing our approach on the Open Annotation Collaboration ontology.
The OAC is also a work in progress but, as luck would have it, they are holding their workshop in Chicago on exactly the same dates as ours (we now have a great line-up, btw, so register soon as places are filling up). Their fundamental principles seem to be exactly what we are looking for though: the ability to connect a target web document with some information about it (in our case, an ancient place).
The basics should look something like this: