Physical geography, or topography, uses precise language to describe the Earth’s surface features. Elevated landforms are defined by their highest point. This uppermost location has several names, and understanding the distinctions helps clarify how these features are measured and categorized. While the terminology is often interchangeable in common conversation, each term carries a distinct geographical meaning.
Primary Terminology for the Highest Point
The most direct answer to what the top of a hill is called is the summit, formally defined as the single highest point on any elevated landform. Mathematically, a summit represents a local maximum in elevation, meaning it is higher than all surrounding points. This term applies equally to the highest point of a small hill or the peak of the world’s tallest mountain.
Another common term, peak, is often used synonymously with summit, though it sometimes implies a more pointed or sharp top. A single mountain mass may have several distinct peaks, but only one true summit. Less frequently, apex is used as a formal synonym for the uppermost point where ascending lines converge.
The term crest typically describes an elongated feature, referring to the top line or boundary of a hill or mountain. A crest is the continuous line of high ground, often forming a ridge, and is not necessarily the single highest point. While the summit is a single point, the crest is a linear feature that may contain the summit at its highest location.
Defining the Difference Between Hilltops and Mountaintops
The terms used for the top of the landform may be similar, but classifying the landform itself as a hill or a mountain is based on different criteria. There is no single, globally accepted technical definition, though historical and local standards provide a general distinction. A frequent guideline, particularly in the United Kingdom, suggests that a mountain is any summit at least 2,000 feet (610 meters) high.
The United States Geological Survey does not maintain an official height cutoff, recognizing that the distinction is often subjective. Historically, an informal elevation of 1,000 feet (305 meters) was sometimes used to separate a hill from a mountain in the US. However, absolute elevation is often less informative than the landform’s height relative to its surroundings.
The physical difference lies more in the local relief and the steepness of the slopes. Local relief is the difference between the highest and lowest elevations within a relatively small area. Hills generally have a smoother profile and rise gently, while mountains are characterized by steeper, more dramatic slopes and rugged terrain. Steepness and prominence are the most reliable indicators distinguishing a mountain from a hill.
Adjacent Features and Related Topographical Terms
The landscape surrounding a hill or mountain summit is described using other precise topographical terms. A ridge is an elongated section of high ground that typically connects two or more peaks or summits. This feature is formed by the intersection of two sloping surfaces and can vary greatly in steepness and width.
A saddle or col is the lowest point along a ridge that lies between two adjacent peaks. This feature resembles a horse saddle and often provides the most accessible route for a trail or pass to cross a mountain range. The term col is generally considered the more formal geographical term for this low point.
A technical measurement called prominence describes how independent a peak is from its neighbors. Prominence is calculated as the vertical distance between a summit and the lowest point on the contour line connecting it to a higher peak. This lowest connecting point is known as the key col or key saddle. A hill or mountain with high prominence is considered more significant because it rises substantially above the surrounding terrain.