The area that more or less encompasses the modern-day country of Italy. Though Rome itself is within Italy, any threads that might take place outside of the city proper (small villages, villas, in Naples, etc.) are put in here.
Though the Romans did not use the word "Africa" to refer to the whole continent as we do today, this listing encompasses all of modern North Africa: from Morocco to Egypt. Any threads taking place in Carthage or Alexandria should be posted here.
This term is often used to mean different areas, but for our purposes the region of Illryia encompasses the provinces of Pannonia, Dalmatia, and Illyria. It is modern-day Austria, Solvenia, Croatia, Bosnia, and Serbia.
The area of Thrace encompasses the lands to the east of Greece, going to the Bosporus Straight that separates Europe from Asia. The city of Byzantium is within Thrace. Dacia is the newly-conquered province, still rife with problems.
The geographical regions of Asia (Asia Minor) and Syria (the "Middle East") were some of the richest provinces in the Roman empire. In particular the city of Antioch within Syria was considered the "Rome of the East" and was the base for almost all of the Eastern Legions.
Judea was tricky in terms of Roman ownership because though it was a client-kingdom, it also enjoyed quite a bit of autonomy. It was considered a province by Rome -- with a procurator being put in place there -- yet it was also recognized as an independent kingdom. The holy city of Jerusalem is within this region.
Though not a province, the Mare Nostrum (the Mediterranean) is the main 'highway' of travel between the various provinces of Europe and Asia. Any threads that may take place at sea should be placed within this sub-forum.