Indicates a community that is historic and no longer exists. While a few buildings, houses or some ruins might still exists, most historic communities are gone with no trace.
ORP
Indicates what we call an Orphan. An Orphan is the situation where we have a name with very little information or we're uncertain whether the name is a community, a post office or might be railroad related such as a siding or station.
PO
While a post office name generally indicates the community in which it is located, other PO names don't. In this case,
we have a PO name but not the community in which its located.