The municipal unit of Ithomi covers 90.428 square kilometers of the Messenian interior, extending from west of Mount Ithome through the valley to the east, as far as the Mavrouzumena River — a tributary of the Pamisos, Messenia's principal river. The Mavrouzumena flows from north of Ithome in roughly its natural configuration; it is dammed just below the community of Valyra, the largest settlement in the unit and the former seat of the old deme. Some maps label this village Valyra-Ithome to distinguish it from other places sharing the name, a small accommodation to a long history.

The land given to agriculture, arboriculture, and viticulture looks much as it has for centuries. Olive groves and vineyards cover the lower slopes and fill the valley floors. The Mavrouzumena runs between its banks, still useful, still marking the territory that organized itself around it before anyone drew an administrative boundary.

No community within the municipal unit is actually called Ithomi today. The name belongs to the unit as a whole, inherited from the mountain. What the unit does contain — and what gives it a significance far beyond its modest size — is the site of ancient Messene, officially called Archaia Messene: the ruins of the great walled city founded in 369 BC on the lower western slopes of Ithome.

In the early years of the ancient city's existence, the site was called Ithome. A somewhat larger surrounding territory was known as Messana. Over centuries the names shifted, the city grew, and eventually the ruins became what they are today: one of the most extensively excavated archaeological sites in Greece, a sprawling complex of Hellenistic and Roman remains still being uncovered. The village of Mavromati sits inside the ancient walls, its population constituting the registered population of Archaia Messene. It is a peculiar arrangement — a living village within the foundations of an ancient capital — and one that the Messenian landscape seems to find entirely natural.

The word demos — the Greek root of democracy — originally meant the people organized as a geographic community. Demes appear in the Iliad; they predate Athens and its famous experiment by centuries. The municipal unit of Ithomi traces a continuous line of geographic governance from those ancient units, through Roman provincial administration, through Byzantine restructuring (the emperor Leo VI formally abolished the Roman administrative structure in the ninth century), through Frankish occupation, Ottoman rule, and into the modern Greek state.

Each transition reshaped the administrative hierarchy while the underlying settlements stayed roughly where they were. The current structure dates to the Kallikratis reform of 2010–2011, which reorganized Greece's municipalities and folded the former deme of Ithomi — which had its seat at Valyra — into the larger municipality of Messini. The communities themselves, however, kept their populations and their names. Governance changed; the land did not.

Archaeology has complicated the popular image of ancient Messene as a city frozen in its founding moment — a perfect Theban gift, delivered in 369 BC and left untouched for archaeologists to discover. The reality is more interesting. Epaminondas reconstituted the city-state of Messenia with Messene as its capital, and the city served as capital for several hundred years, until the Byzantine Empire shifted the regional seat eastward across the mountain. The walls were so well built that they never needed full reconstruction — only repair. But the interiors changed constantly, rebuilt and remodeled over the centuries by generations of inhabitants.

The ruins visible today, in other words, are not a single-period snapshot but an accumulation: layers of Hellenistic, Roman, early Christian, and Byzantine habitation laid down over what Epaminondas established. The municipal unit of Ithomi administers this accumulation, hosting the site as a living archaeological zone rather than a static monument. Excavations continue. The mountain watches.

The small communities of the Ithomi municipal unit — Valyra, Aristodimio, and the others — live the ordinary agricultural life of the Messenian interior: olives, vines, orchards, the Pamisos water running between engineered dikes in the lower valley. What makes their situation unusual is the context. Most farming communities sit near ruins. Here, the ruins are the reason the name exists at all. The municipal unit is named for a mountain named for an ancient settlement, and within its boundaries the most dramatic chapter of Messenian history is still being excavated, literally, from the ground.

Travelers who come to see the great walls of ancient Messene enter the municipal unit of Ithomi, park near Mavromati, and walk into the bowl of the ancient city. The mountain rises above them. The spring still emerges from the rocks at the village center. The Pamisos collects the Mavrouzumena somewhere in the valley below. The ancient irrigation channels from the klepsydra spring are still visible in the rock. Antiquity here is not fenced off and separate. It is the ground itself.