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The Rocky Mountains are the main mountain range in the Cordillera system of North America, in the west of the USA and Canada, between 60 and 32° N. w.

Rocky Mountains stretch for 4830 kilometers from north to south from the northern point in the province of British Columbia (Canada) to the state of New Mexico in the southwest of the United States. The width of the mountains reaches 700 kilometers. The Rocky Mountains are a natural watershed between the basins of the Pacific and Atlantic Oceans. In the Rocky Mountains, the rivers of Missouri, Colorado, Rio Grande, Snake, Arkansas and many others originate. Rocky Mountains were formed from 80 to 55 million years ago in the era of Laramie’s orogeny. Since then, under the influence of water and glaciers in the mountain range spectacular valleys and peaks were formed. At the end of the last ice age, people began to colonize the Rocky Mountains. After several expeditions, such as the journey of Alexander McKenzie or the expedition of Lewis and Clark, the Rockies began to settle; minerals and furs gave rise to the initial economic development of the mountains, despite the fact that the Rocky Mountains remained a sparsely populated area. Currently, most of the territory of the Rocky Mountains is protected by national parks and forest lands. Rocky Mountains – a popular place for tourists, especially for hiking, mountaineering, fishing, hunting, skiing, snowboarding and others.

The name «Rocky Mountains» was given by the Canadian pioneer of French origin Pierre Gauthier Varenne de la Verandry after he crossed the river Pierre Jaune (today it is Yellowstone – the river of yellow stone) on January 1, 1743. Alexander Mackenzie crossed the mountains in 1793 and named them «Stony Mountains». In the second half of the XIX century, the mountains were returned to the previous name.

The Northern Rocky Mountains (north of 45° N) are mainly composed of granites up to 3954 m in height (Robson Mountain); The southern Rocky Mountains, or the Rocky Mountains of the United States, consist of short ridges composed of sandstones, shales, limestones, up to 4,401 m (Albert Mountain – the highest point of the Rocky Mountains). There are extensive deposits of molybdenum, copper, gold, silver, polymetals, oil, and coal. Volcanic phenomena are observed: geysers, thermal springs, and earthquakes.

In the Rockies is a typical mountain climate. The average annual temperature in the valleys is within 6° C. In July, the warmest month, the average temperature reaches 28° C. In January, the average temperature is about -14° C, and this is the coldest month of the year. The average annual precipitation is about 360 mm.

In the Rocky Mountains in the summer it is usually warm and dry, as rain clouds from the west linger on the mountain ridge on its western side. The average temperature in summer is 15° C, and the average amount of precipitation is about 150 mm. Winters are very long and cold, with an average temperature of -2° C, and an average thickness of snow cover of 29 cm. In the spring, the average temperature is 4° C, and the precipitation is 107 mm. In autumn, the average rainfall is 66 mm and the temperature is about 7° C.

Vegetation – mainly forests, mountain-taiga in the north and pine in the south. The height of the forest boundary is from 1500 m (in the north) to 3600 m (in the south), higher – alpine meadows and eternal snow.

In the forests grow spruce, pine and fir, on the lower tiers, they mix with birches and white maple. Most of the mountains of the Arctic latitudes are covered with dwarf birches. On taiga soil not only coniferous, but also deciduous trees grow: birch, poplar and aspen.

In the valleys there are steppes and semi-deserts.

High-altitude animals here are snow goats, thick-nosed, elks and foxes. In the areas below, there is a marmot, a hare-hare, a black-tailed meadow dog and a coyote.

Most of the birds living in the Rocky Mountains are flying. In the summer months they feed the chicks here. Constantly in the mountains there live a three-toed woodpecker, a white partridge, some species of finches and owls.

In the Rockies are national parks Jasper (Canada), Banff (Canada), Yoho (Canada), Kootenay (Canada), Waterton Lakes (Canada), Glacier (USA), Yellowstone (USA), Rocky Mountain (USA).

Great Plains.

Great Plains – a piedmont plateau in the US and Canada, east of the Rocky Mountains. The height is about 700—1800 m above sea level. The length is about 3600 km, the width is from 500 to 800 km.

On the Great Plains are the territories of the Canadian provinces of Alberta, Manitoba and Saskatchewan and the American states of New Mexico, Texas, Oklahoma, Colorado, Kansas, Nebraska, Wyoming, Montana, North Dakota and South Dakota.

Great plains from north to south are divided into such major zones as the Missouri Plateau, the central High Plains, the Llano Estacado Plateau and Edwards. In some areas erosion of rocks is observed (these are the so-called bad lands, «badlands»). In the south they pass to the Mexican Highlands.

The climate within the plains is continental. Vegetation is mostly steppe.

On the plateau territory, wheat production is developed (the Great Plains are often called the «World Bread-Bread»), pasture cattle breeding. The US began to develop this area after the Louisiana purchase (1803). As early as 1820, researchers recognized these lands as unsuitable for life.