In terms of nature, Nepal can be divided into three main regions, the Terai, the Middleland and the highmountain region. The socio-economic, cultural and ethnic stratifications of the country are also linked to this structure.
The Terai, with altitudes of 70 to 150 meters, forms the Nepalese part of the lowlands of Ganges. Over the past 50 years, it has developed into an important economic and settlement area. Although Terai accounts for only 14 percent of the country’s surface area, 47 percent of the population live there. Fertile soils with little risk of erosion, a frost-free climate all year round and good irrigation possibilities make the Terai the most valuable agricultural region.
Almost all industrial settlements outside the Kathmandu valley are also located on this plain. The Mahendra Highway runs through the Terai as the only road that provides an east-west connection. Nine domestic airports are located in Terai and offer a direct flight connection to Kathmandu.
The Siwaliks and the Mahabharat chain form the transition from Terai to the Mittelland, which reaches altitudes of up to approximately 3000 metres. The Middleland has a very strongly structured relief. Factors such as microclimate, soil and geomorphology vary in the Central Plateau in a small area, so that the conditions for settlement and agriculture also vary greatly. Nevertheless, the Central Plateau is Nepal’s ancient heartland. 45 percent of the population live here on 30 percent of the country’s surface area.
Due to the high relief energy, the Central Plateau is highly hostile to traffic. Only the Kathmandu and Pokhara valleys and some mountain villages have road access. Kathmandu is the only international airport in the country.
Almost all settlements in the high mountain region are concentrated in the valleys. Summer settlements with pasture farming reach up to 5000 meters. The extremely high relief energy and the high monsoonprecipitation (over 5000 millimetres) on the southern slopes contribute to soil erosion and make agriculture difficult.
The northern sides of the main chain of the Himalayas, which lie in the rain shadow, receive very little precipitation (less than 200 millimetres), so that agriculture is hardly possible. Forestry is an important pillar of mountain farming. Overall, the high mountain region is a food deficit region. The most important external source of income is tourism. Roads are not available. Only four domestic airports connect the mountain region with the outside world.
Due to its central location in the heart of the Asian high mountains and the great contrasts of the landscape (high mountains – lowlands), Nepal has different climate zones. In all parts of the country, however, there is a strong monsoon influence, which brings with it seasonal periods of precipitation. During the monsoon season, which lasts from June to mid-September, rainfall continues throughout Nepal, which can also lead to sudden floods and landslides, which in turn hinder travel. However, such disabilities are normally not to be expected during the travel dates selected by us. During the classic travel seasons in the pre-monsoon and post-monsoon (March to May and October to November) as well as in January and February the weather in Nepal is usually friendly and the precipitation frequency and amount is rather low. Afternoon cumulus clouds and the resulting precipitation are possible, but periods of bad weather rarely last longer than three to four days and do not cause excessive precipitation in the valleys.
The weather conditions in Nepal depend on the season and in the mountains additionally on the altitude. For this reason, it is difficult to make precise temperature forecasts for the trekking routes. In general, the weather is just as unpredictable in Nepal as it is here.
Essentially, the year can be divided into four seasons, as here: Spring (late February to May), monsoon season (June to mid/end-September), autumn (October to November) and winter (December to mid-February).