The Territory and Environment of the Alban Hills



From a geographical point of view, the territory commonly known as the "Castelli Romani" corresponds to the volcanic complex of the Colli Albani (Alban Hills), located a few kilometres southeast of Rome. From a geological point of view, the Alban Hills are what remains of the ancient Latium Volcano, formed throughout a very long period between 630.000 and 20.000 years ago with a process that can be substantially divided into the following three parts:

• Initially, an intense volcanic eruption formed an imposing volcanic cone with a base of 60 kilometres in diameter; the upper border of this enormous volcanic crater collapsed at a later stage, creating the wide caldera, of which only the north eastern edge (Monte Tuscolo and Monte Artemisio) remains today;

• After a long interval, the eruption began again and forming a smaller cone inside the caldera, of which the central part is known today as "Campi di Annibale", while a further two secondary cones gave rise to the existing Monte Cavo and Colle Iano;

• The last stage (known as the hydromagmatic phase due to the violent explosions caused by the contact of underground waters with residual pockets of incandescent magma) formed along the south-eastern border of the original crater several other craters, which later became volcanic lakes; only two of these are conserved today (Lake Nemi and Lake Albano) while others have been dried out and are now valleys dedicated to agriculture (Prato Porci, Pantano Secco, Valle Marciana, Laghetto, Vallericcia).

The altitude range of the territory of the Alban Hills varies from 47 mamsl (in the town of Montecompatri) to 956 mamsl (Maschio delle Faete in the town of Rocca di Papa) with the majority of the towns at hill level between 300 and 700 mamsl.

Since the 17th century, the natural type of forests dominating the territory of the Alban Hills, according to altitude, were:

The Holm Oak Wood, typical of the Mediterranean vegetation region that reaches as far as 200-300 mamsl;

The Mixed Downy Oak Woods, typical of the sub-Mediterranean vegetation region that reaches 400-500 mamsl;

The Mixed Broadleaf Wood, (Oak, Lime, Maple) typical vegetation of the foothill region that reaches 700-800 mamsl;

The Beech wood, typical of the mountain vegetation region, above 800 mamsl;

The extensive chestnut woods that actually cover the complex of the Alban Hills are not a native vegetation of the area but the result of constant human activities in the area that have enormously increased in the last three centuries since the first settlements.

Human interference had gradually substituted the above-mentioned natural woods with profit-making cultivations:

Vineyards and Olive Groves, in regions up to 400-500 mamsl that substitute the holm oak and the mixed down oak woods;

Chestnut Woods, cultivated by coppicing, in higher altitude regions, replacing the mixed woods of oak, lime and maple trees and beech wood.

There are remaining patches of original local forest vegetation that can be identified in several towns of the Castelli Romani. The most important are the following:

• The Bosco dei Cappuccini and Lago Albano - (Albano Laziale)

• The Parco di Villa Chigi (Ariccia)

• The Macchia dello Sterparo (Frascati)

• The Bosco della Madonnella (Grottaferrata)

• The Bosco Ferentano and the Parco Colonna (Marino)

• The Macchia del Piantato (Monte Compatri)

• The Bosco del Lago di Nemi and Vallone Tempesta (Nemi)

• The Bosco di Monte Cavo and the Maschio delle Faete (Rocca di Papa)

• The Bosco del Cerquone (Rocca Priora)

• The Bosco Artemisio and Maschio d'Ariano (Velletri)

The fauna that inhabits the territory of the Castelli Romani is plentiful and interesting.

Birds are the animal category most found in the area, with over a hundred species belonging to several different orders, among which the Passeriformes is undoubtedly the most generous in terms of families: titmice, robins, wagtails, blackcaps, chaffinches, redstarts, gold-crests, winter wrens, goldfinch, long-tailed tits, wood nuthatches, larks, blackbirds, starlings, swallows, orioles, crows, jays, magpies, to name only those that are easy to observe.

There are also other kinds belonging to various orders and families, which are worth noting, for example quails, partridges, red-breasted nuthatches, green-peak and red-peak woodpeckers, hoopoes and cuckoos.

Not to be forgotten are the plentiful migrating waterfowl that visit the banks and waters of Lake Nemi and Lake Albano: mallards, coots, tufted duck, great crested grebes, cormorants and common shags.

Finally, there are numerous and interesting birds of prey, day-flying (buzzards, kestrels, sparrow hawks) and night-flying (small owls, barn owls, big owls, tawny owls, horned owl).

Among the wild mammals that inhabit the woods and countryside of the Alban Hills we can point out (without naming them all) the wild boar, foxes, martens, weasels, badgers, hedgehogs, porcupines, hares, dormice, moles, voles, shrew mice, bates, squirrels and dormice.

Finally, it is worth remembering among numerous reptiles the bright green lizards, the dangerous vipers and the harmless grass snakes and blacksnakes. While among the amphibians it is worth mentioning some rare species of the Pantano della Doganella (Rocca di Papa): the fire salamander, the spectacled salamander, the smooth newts and the great crested newts.