Lake Garda
Lake Garda is the largest lake in Italy. It is a popular holiday location in northern Italy, between Brescia and Milan to the west, and Verona and Venice to the east. The lake cuts into the edge of the Italian Alps, particularly the Alpine sub-ranges of the Garda Mountains and the Brenta Group. Glaciers formed this alpine region at the end of the last ice age. The lake and its shoreline are divided between the provinces of Brescia, Verona and Trentino.
Etymology
In Roman times the lake was known as Benacus and by some it was revered as god Benacus, the personification of the lake, sometimes associated with the cult of Neptune. Today it is better known as Lake Garda, a toponym of Germanic origin attested since the Middle Ages and deriving from that of the homonymous town on the Veronese shore of the lake, which, together with another famous locality of the lake, Gardone Riviera, and others less known – such as Gàrdola, Gardoncino, Gardoni, Guàrdola and Le Garde – testifies to the Germanic presence in the area that dated from the 6th to the 8th century CE, in particular, the Lombard one. The name Garda is evolved from the Germanic word warda, meaning "place of guard", "place of observation" or "place of safety".The classic toponym of the lake, or Benācus lacus, is almost certainly of Celtic origin, therefore prior to romanization, and should derive from bennacus, comparable with the Irish bennach, which means "horned". The term may derive from the many promontories of the lake.
Geography
Morphology and hydrography
The northern part of the lake is located in a depression that insinuates itself inside the Alps, while the southern part occupies an area of the upper Pianura Padana. The shape is typical of a moraine valley, probably having been formed under the action of a Paleolithic glacier. Although traces of the glacier's actions are evident today, in more recent years it has been hypothesised that the glacier occupied a previously existing depression, created by stream erosion 5 to 6 million years ago.A characteristic of Garda is the limited size of the hydrographic basin compared to the lake surface: at a length of of the lake corresponds the of the basin, while the respective widths are and. The eastern watershed of the Benacense basin has a direction parallel to the axis of the lake, while the western one has a more sinuous course. Within the basin, the major peaks are Presanella and Adamello. Morphologically, the Garda hydrographic basin can be divided into four areas: the plain of about, the lake surface of about, the western portion of about 500 km2 and the eastern one of approximately.
To the south of Lake Garda, between Brescia, Mantua and Verona, a large morainic amphitheatre develops: a succession of hilly circles with small flat areas interposed, in some cases marshy, originated thanks to the transport and storage action of the great Garda glacier. These morainic deposits were formed during the glaciations Günz, Mindel, Riss and Würm: very limited morainic deposits are attributed to the two oldest, Günz and Mindel, while the outer morainic circles are attributed to the Riss glaciation and the inner ones to the Würm glaciation. The morphology of the hills is gentle and with delicate lines; from the highest points, it is possible to perceive the relationships that link the hills to the mountains as well as the circular amphitheatre shape of the hills, which seem to embrace the southern part of the lake.
The main tributary of Lake Garda is the Sarca River, others include the Ponale River, the and various streams from both mountainsides, while the only outlet is the Mincio River. The subdivision is created by the presence of a fault submerged between Sirmione and Punta San Vigilio which is almost a natural barrier that hampers the homogenization between the water of the two zones.
If the water level of the Adige River is excessive, water is diverted to the lake through the Mori-Torbole tunnel.
Geology
The Lake Garda area is considered one of the most seismic in Italy. The oldest known earthquake that struck the Garda region seems to have occurred in 243 : it was so disastrous that the city of Benaco, located where Toscolano Maderno stands today, suddenly disappeared. The disappearance of the town is probably due to the cracking and landslide of the mountain above Toscolano, which caused the flooding of a small lake enclosed by the mountains, whose waters submerged the populous town.Other earthquakes, more or less intense, followed one another periodically: in 793, when according to the chroniclers it caused great calamities, especially in the Baldo area; in 1457, during which a mountain above Salò lowered; in 1703, when it caused the fall of numerous houses and caused many victims; in 1810, an earthquake particularly hit Malcesine where it caused a clouding of the waters and the formation of a crack long and wide in the town square; in 1836, when the tremors caused some landslides in Mount Tomè, in the northernmost part of Monte Baldo, which in turn caused a strong eruption of water.
In 1866 a rather long period of seismic agitation began in the Baldo area, with earthquakes of varying intensity, tremors, shaking and other phenomena of lesser importance, which saw as the most important event the earthquake of 5 January 1892, which shook the entire Garda region with extraordinary violence, causing the fall of chimneys and walls.
Other earthquakes more recently hit Salò and its surroundings, in particular, the earthquake of 31 October 1901 caused widespread damage to buildings, some collapses and cracks in the ground, while another earthquake in 2004 caused damage to some buildings.
Islands
The lake has also numerous small islands and five main ones, the largest being Isola del Garda. Nearby to the south is San Biagio island, also known as the Isola dei Conigli. Both are offshore of San Felice del Benaco, on the lake's western side. The three other main islands are Isola dell'Olivo, Isola di Sogno, and Isola di Trimelone, all farther north near the eastern side.Climate
The particularly mild climate favours the growth of some hardy Mediterranean plants, including the olive tree, parasol pine, mediterranean cypress, chinese windmill palm and Canary Island Date Palm. Some hardy citrus trees, such as hardy lemons and satsuma can also be found, which are extremely rare at this latitude. In ancient times, poets like Catullus wrote about "Lacus Benacus" with its mild climate vivified by the winds. The lake is oriented from north to south towards the Po Valley, so many winds typical of the lake are the result of a difference between lower and higher altitude temperatures. Due to this, winds are generated that descend from the mountains to the plains in the morning and go back to the mountains in the afternoon. The bottleneck formed by the lake basin affects the timing of the winds, many of which happen on a regular daily basis. The winds are all named, most in regional Italian dialect so a single wind may have different names.Fauna and flora
Lake Garda is rich in biodiversity. Salmo carpio, also known as the carpione is a rare salmonid fish endemic to Lake Garda. It has been introduced to a number of other lakes in Italy and elsewhere but unsuccessfully in all cases. The population in Lake Garda has been strongly declining, and is considered critically endangered. The main threats are due to overfishing, pollution and possibly competition from introduced species such as Coregonus and other Salmonidae.Adult lake trout outside the mating season are silvery with very few black spots on the body and almost none on the head. During the mating season, some males develop a dark mottled body colouration. Garda lake trout reach a length of up to. They live primarily in depths of. They feed on zooplankton and bottom-dwelling crustaceans in summer. Males and females reach sexual maturity at two or three years. The mating takes place every one to two years. The spawning takes place in depth in the vicinity of underwater springs. The maximum age is five years.
Areas around Lake Garda, inhabited since prehistoric times, are an environment of great naturalistic value, with vegetation typical of the Mediterranean climate such as olive trees, vines, lemon trees, agave and other plants, which thrive thanks to the microclimate created by the Garda basin, which makes winter particularly mild. During the spring wildflowers such as primroses, iris, violets and red lilies are born, while in summer some bloom varieties of wild orchids. Thanks to the presence of protected areas, hares and small wild mammals, water birds and birds of prey survive, while ponds and ditches are populated by pike, carp and eels. The herds of cattle, horses and other domestic animals give a bucolic aspect to the hilly landscape.