hill

Hill is a natural rise of the land, typically smaller than a mountain. Definitions vary by region, but a hill usually has a rounded or conical summit and gentler slopes. Heights commonly range from tens to a few hundred metres, and prominence is often used to distinguish a hill from a mountain.

Hills form by several processes. Erosion and weathering can wear down high terrain, leaving isolated elevations. Tectonic uplift, volcanic activity, and glacial sculpting may create hills, sometimes capped by more resistant rock that slows erosion. In glaciated regions, features such as drumlins can appear as elongated hills.

Hills occur worldwide, from rolling chalk downs to volcanic cones and inselbergs. Local terms such as knoll, mound, or hillock describe smaller rises, while larger features are simply called hills in some regions. The distinction between hill and mountain is not universal and often depends on local tradition.

Hill landscapes influence human activity and ecology. They host settlements, fortifications, and agricultural terraces, and are popular for recreation such as hiking and viewpoint tours. Slopes support diverse habitats, although soils tend to be thinner and drier than in valleys. Climate and hydrology on hills can create microclimates that affect vegetation and land use.