The fueguine archipelago is separated from the continent by the Strait of Magellan, including islands and islets with a the total area is 72,000 Km2. The main island is known as Isla Grande with an area of 45,000 Km2. Its limits are established to the west by meridian 68º 36´ longitude west, the Mar Argentino to the east, while the oriental mouth of the strait of Magellan marks the limit to the north and the Beagle Channel to the south. The city of Ushuaia is the capital of the province, considered the southernmost in the world and lies on the north coast of the Beagle Channel and at the foot of the Martial chain, in the middle of the Andes Mountains. The relief is irregular: glaciary valleys, a thousand-year-old peat bogs, hills and valleys. While Río Grande located in the north, has the features of a typical Patagonian city: flat surface with smooth undulations and with the sea and the floodable valleys as the only natural limits.

Glaciers are formed by the low temperatures and the resulting accumulation of snow in the earth's surface. Geologists call glaciations the periods of low temperature and interglacial those of high temperatures. In most cases, glaciations act on the landscape modifying its features and erasing the traces of the previous glaciation. When reference is made to this phenomenon, only glaciations that took place in our era, that is the Quaternary period, are considered. The latest scientific research indicate that almost all of Isla Grande of Tierra del Fuego was covered by ice during the Pleistocene period (100,000 to 20,000 years ago). Not only the southern area was exposed to the effects of the ice, but the seabed occupied today by the Strait of Magellan was occupied by a great glacier. At the same time, the Beagle Channel was occupied by a river of ice with a height of approximately 1,200 meters over the current sea level, with an extension of 200 Km. The effect of the erosion was such that converted it into an inter oceanic channel.

Different minerals have been exploited in our province, some until depleted, as in the case of the gold. The mineral abundance of the region includes: iron pyrite oil, gas, clays and peat bogs among others. The peat bog is vegetal material in state of decomposition on which research has been carried out to determine its potential applications. So far, it has been used in soil improvement. It is found in places with the following characteristics: - Excess of water, that must be constantly renewed. - Permeable soil and subsoil - Rainy climates - Lack of air in the deepest areas of the terrain. The presence of peat bogs is precisely, a fueguine curiosity. These formations are mainly found in the great southern valleys like Carvajal, Tierra Mayor and Moat. The predominant vegetables are the Sphagnum and Carex moss. One of their main properties is the absorption of great quantities of water.

The formation of soils is a constant process in which biotic and abiotic agents participate: The minerals that form the bed rock, like the relief, the climatic conditions, the time elapsed and the predominant vegetation, participate of this phenomenon. In Isla Grande, six types of soils can be differentiated, that are called edaphic domains and occupy well differentiated areas. The same can be identified through an analysis of the relief and its geomorphology. In Tierra del Fuego we find: 1) Top of mountain ranges 2) Hills and glaciary valleys 3) Glacier fluvial valleys 4) Well preserved undulating plains 5) Undulating plains with steep slopes 6) Plains with marine accumulation. Another feature is the presence of permanently frozen soils, also known as permafrost. Factors like altitude, temperature change an exposure to wind, among others, determine the depth of this cold layer of soil. In our province, permafrost is found starting at 700 mm, and can be easily identified since it is marked by a line limiting the forest.

Most of our rivers are born in the Argentine and/or Chilean mountain range and flow into the Atlantic Ocean, the Beagle Channel or the Strait of Magellan. In our province, and according to the relief, we can divide the rivers into Andean and extra Andean. The Andean courses of water are found in the south of Tierra del Fuego, among them we can mention the following rivers: Claro, Valdez, Milna, Pipo, Larsifashas, Lapataia and Olivia, among others. Lakes Yehuin, Fagnano, Escondido, Roca and Chepelmut belong to this category. The main characteristics of the mountain rivers are: - Their sources are found in altitudes where ice and snow melt. - The courses of water are short and with steep slopes of cascades and rapids. - The flows vary, floods are caused by deicing and strong rains. As to the extra-Andean rivers, they are located in the center and northern areas of the island, they are small rivers with little flow due to scarce precipitation. They are of the seasonable type because they transport larger quantities of water during September and December. Río Grande is the most important river of the archipelago, not only by its flow, but by the length that reaches 220 Km. Its source is in Chilean territory and collects tributaries on its way to the Atlantic Ocean.

The eastern sector of the fueguine archipelago can be divided according to its climate into two well defined great environments. The area south of Lake Fagnano is affected by the oceanic cold, while in the northern area we find a cold sub-humid climate. Our island is under the influence of the oceanic mass, and due to the moderating effect of the sea, the minimum temperatures are not that low, and the maximum temperatures are less that in other locations at the same latitude in the northern hemisphere. Another influential factor is the proximity to the Antarctic continent; this generates the emission of cold winds that cause polar fronts that affect our province. The presence of winds is characteristic of the fueguine climate. In Tierra del Fuego, the predominant wind blows from the west quadrant, but in the case of Ushuaia and due to the presence of the mountain range, the wind blows from the southwest quadrant. The mountain range acts as a barrier to the cold air fronts from the Pacific. When these humid winds hit the mountains, they unload great quantities of vapor that precipitates in the form of snow or rain over the valleys and slopes, and the wind continues on with less humidity.

Climatic factors	Ushuaia	Río Grande
Annual average temperature July average January average Daylight in winter Daylight in summer	5,3º C 1º C 9,1º C 6 h 45 min. 17 h. 23 min.	5,5º C -0,2º C 10,1º C 7 h. 35 min. 17 h. 05 min.