Violent prehistory
A caldera is formed when a volcano collapses. The collapse is triggered by the emptying of the magma chamber beneath the volcano, usually as the result of a large volcanic eruption. One famous example is Santorini's caldera, formed in the Minoan eruption around 1600 BCE
Now the Alban volcanos are dead, although they still emits large amounts of carbon dioxide that can potentially reach lethal concentrations. 29 cows were killed in 1999 and eight sheep were killed in a similar incident in 2001.
In this area, several catastrophic events like sudden mudflows (lahars) from the hillside and rising of the water level have occurred in recent times, probably up to less than 7000 years ago, and this may have prevented human settlements. Of particular interest is the description reported by several ancient historians (from Plutarcus to Titus Livius) of a sudden lake overflow from the Albano Lake, occurring in the IV century B.C., an event that induced the excavation of a drainage tunnel that has since kept the lake level 70 m below the lowest crater rim. This tunnell is only one of a series of impressive works, draining the lake of Albano and other lakes in the area, including Lake Nemi. The Nemi-tunnell, Emissarium, is 1653 m long, and most people say that they were made by the romans, but some argues that it must have been carried out by early civilisations, well before the Romans conquered Italy and governed the territory. This is based on the the fact that the techniques used in the excavations are similar to findings in Greece, in the tunnel of Samos, and in the outlet of Kopais, the latter which could be attributed to the Mycenaean civilisation, namely to the 12th century BC. It would be reasonable to counter this: Techniques can be learned! In any case, it may be safe to say that there must have been a transfer of culture.
So the tunnels gives us the first clue that Nemi are of pre-roman origin and connected to Greece and the eastern mediterranean regions, a theme that we shall return to later.
Alba Longa, the mother city of Rome
Another clue comes from the myths and history of Rome where the kingdom of Alba Longa has a very important place. After the destruction of Troy, many refugees were thought to have fled the city, among them was Aeneas, the the son of prince Anchises and the goddess Aphrodite. Aeneas was a great Trojan hero second only to the mighty Hector. Aeneas's travels brought him eventually to Latium, the homeland of the latin people. This is the region now called Lazio.
Soon after arriving in Italy, Aeneas made war against the city of Falerii. But Latinus, king of the Latins (who, according to Hesiod, was the son of Odysseus and Circe), welcomed Aeneas's army of exiled Trojans and let them reorganize their life in Latium. His daughter Lavinia had been promised to the king of the Rutuli, but Latinus preferred to offer her to Aeneas. According to legend Alba Longa was founded by the son of Aeneas, Ascanius (or Iulus), and from him there is said to have sprung a dynasty of Alban kings (see the Family tree of the kings of Alba Longa) , one of the last was Numitor who was the grandfather of Romulus and Remus, the mythical founders of Rome.
Until today the location of Alba Longa has never been established with certainty. The site has been at various times identified with the convent of S. Paolo at Palazzola, near Albano, or with Coste Caselle, near Marino, or finally witth Castel Gandolfo. There is also a theory that Alba Longa means the western crater rim of the Albano Lake, based upon the observed light belt cast there soon after sunrise.
The Latin League and war with Rome
Latium at that time was a mixture of different nations and small tribes, among which was the Latins. Actually, they were not a single nation, but rather a confederation uniting many tribes of common Italic origin. They spoke the same language, led the same way of economic life and worshipped the same deities. Due to Italic traditions, and also to later Etruscan influence, Latin towns and villages composed the urban alliance, the Latin League, which was both military and religious, and led by the city of Alba Longa, where all Latins used to gather to the sacred temple on a mountain and to the common meeting. The official leader of the alliance was the king of Alba Longa.
At first Rome was probably one of these cities, but as Rome's power increased, the two cities fell into conflict, and finally under King Tullus Hostilius (around the middle of the 7th century BC), a war between them was settled by the famous combat of the Horatii and the Curiatii; Alba was destroyed, never to be rebuilt, and her inhabitants were transferred to Rome, where the Caelian hill was given to them. The increasing power of Rome gradually led to its domination of the league. The renewal of the original treaty in 358 BC formally established Roman leadership and eventually triggered the outbreak of the Latin War (343 BC—338 BC). Following the Roman victory, the league was dissolved, and Rome was an it's way to imperial power.
Religion and recreation
On the top of the Monte Cavo was a very ancient shrine consecrated to Jupiter Latiaris. Florus (2nd century) states that the site was selected by Ascanius, who, having founded Alba, invited all the Latins to celebrate sacrifices there to Jupiter, a custom which eventually led to the annual celebration there of the Feriae Latinae, at which all the cities that belonged to the Latin Confederation would gather under the aegis of Alba, sacrificing a white bull, the flesh of which was distributed among all the participants..
In 222 year of Rome Tarquinius Superbus legendary King of Rome fixed a temple common to the Latins, to the Hernici and the Volsci on the Mons Albanus, where every year there were celebrations in honor of Jupiter Latiaris. A triumphal procession, along this sacred way, the Via Triumphalis, left the Appian Way at Ariccia and climbed ut 450 m to the hillside. More than 5 Km of this way is well preserved through the woods. The temple has not survived, but it may be no coincidence that in the early Middle Ages, a hermitage was built by a Dalmatian hermit devoted to St. Peter, that replaced the pagan temple. It was visited by Pope Pius II in 1463, and subsequently by Pope Alexander VII, and later converted to a monastery,
This monastery also had many prominent guests. And this is certainly no coincidence, because the hills, especially around the shores of the lakes, have been popular since ancient times as a way to escape the heat and crowds of Rome, and there are many villas and country houses to be seen. Since 1626 the Pope has had his summer residence at Castel Gandolfo, and even Julius Caesar, appreciated the beauty of the place and commissioned a villa to be built at Nemi.
The Sacred grove
In antiquity the Alban hills were thickly wooded, the original forest was probably of beech trees and scrub, and down by the shore of lake Nemi was a Nemus, or a Sacred Grove. The Celts called such a place a Nemeton, and the earliest sanctuary was just a clearing in the wood which was turned into a templum, a consecrated area. The principal deity in the sanctuary was Diana (or Diana Nemorensis that she was called here), but also the greek hero Hippolytos, who had been transformed into a minor local deity bye the name of Virbius was worshipped. A peculiar feature of this cult was the Rex Nemorensis who reigned as the King of the Grove. This king was a runaway slave that ruled until he was challanged and beaten by the next King. A study of this cult served as the seed for Sir James Frazer's seminal work on the anthropology of religion, The Golden Bough.
It is uncertain how old this cult is, but as far as the around 500 BC, the sanctuary was for a period the League Sanctuary for of the Latin towns. It was not just of local significance, since men of power fro other cities, particularly Rome, travelled to the Sacred Grove at Lake Nemi to present her with rich gifts. Around 300 BC the first temple was built, and later there were added bathing facilities and a theatre. We do not know where the money came from, but the building activity show that the Sanctuary was well provided for.
Caligulas sunken ships
But there is more: early in the 1930s two ships were recovered from the mud of lake Nemi. It was not just any ships - they were over 70 m long and 20 wide, and had a gross tonnage of up to 1100 tonns. The deck of oak were covered with a marble mosaic floor. Findings showed that there had been running water, heating, and possibly even bathing facilities. These ocean-going, floating palaces are attributed to Caligula, maybe the most decadent of all the emperors.
The boats were finally salvaged under orders of Mussolini as an attempt to relate himself to the Roman Emperors of the past. From 1936 the ships was exhibited in a a newely constructed museum with a "hangar" for each, and here it was possible to admire them for the next nine years, until the 31st may in 1944, when then were taken by the flames lit by retreating german soldiers.
We do not know wether the ships are connected with the cult of Diana, but we may certainly take them as a symbol that there is more under the surface than meets the eye at Nemi, and more surprices to be had.
REFS
The mains source is In the sacred Grove of Diana, by Pia Guldager Bilde et al. Linked websites.
