# What's the difference between a mountain, a hill and a peak?

> There's no official height that makes a hill a mountain. What the USGS says, the old 1,000 ft rule, the UN's working definition, and where peak and summit fit in.

Source: https://mountainidentifier.org/guides/mountain-vs-hill-vs-peak
Last updated: 2026-10-09

**There's no official height that turns a hill into a mountain. The US Board on Geographic Names doesn't define either word, and old British and American 1,000 ft rules were dropped long ago. In practice a mountain is higher, steeper and stands out more from its surroundings. A peak or summit is the high point itself; one mountain can have several.**

## What the official bodies say

In the United States, the [USGS states plainly](https://www.usgs.gov/faqs/what-difference-between-mountain-hill-and-peak-lake-and-pond-or-river-and-creek) that there are no official definitions for generic terms like mountain, hill and peak. Its names database sorts features into broad categories only to make searching easier. A feature's name is whatever it's officially called, so Kansas has hills and Pennsylvania has "mountains" that would barely register in Colorado.

Britain and the US both once used a height rule: 1,000 ft (305 m) and above was a mountain. Both dropped it, and accounts differ on exactly when. In British hillwalking today, 2,000 ft (610 m) is a common informal threshold, but it's a convention, not a rule.

## The closest thing to a working definition

When scientists need to map "mountains" consistently, for forest or water studies, they use rules based on height, slope and local relief. The most cited is from UNEP's World Conservation Monitoring Centre, known as the Kapos classes and described in the [UN's SDG indicator metadata](https://unstats.un.org/sdgs/metadata/files/Metadata-15-04-02.pdf):

| Elevation | Counts as mountain if... |
| --- | --- |
| 2,500 m and above | Always |
| 1,500-2,500 m | Slope of at least 2 degrees |
| 1,000-1,500 m | Slope of at least 5 degrees, or more than 300 m of local relief |
| 300-1,000 m | More than 300 m of local relief within 7 km |
| Below 300 m | Never |

The interesting part is the middle: below 2,500 m, it's not the height that decides but how much the land rises around it. That matches most people's instinct. A 900 m summit rising straight out of the sea feels like a mountain; a 1,400 m bump on a high plateau doesn't.

## Peak, summit and mountain

- **Mountain** is the whole landform, from its base to its top.
- **Summit** is the highest point of a mountain or hill.
- **Peak** is often used for summit, but it can also mean any high point, including subsidiary tops on the same mountain.

Whether a subsidiary top counts as its own peak is usually settled by [prominence](https://mountainidentifier.org/guides/what-is-mountain-prominence): how far it rises above the saddle joining it to something higher. That's how peak lists decide what to include, as our [peak bagging guide](https://mountainidentifier.org/guides/peak-bagging-for-beginners) explains.

## How high are the world's summits, really?

If "mountain" brings to mind the Alps or the Rockies, the data is a useful corrective. OpenStreetMap volunteers have mapped hundreds of thousands of named summits, and most are modest. Here's how the 687,599 summits in our app's database break down by elevation:

| Summit elevation | Summits | Share of those with an elevation |
| --- | --- | --- |
| 0-1,000 m | 306,920 | 59.9% |
| 1,000-2,000 m | 122,314 | 23.9% |
| 2,000-3,000 m | 56,492 | 11.0% |
| 3,000-4,000 m | 16,309 | 3.2% |
| 4,000-5,000 m | 5,925 | 1.2% |
| 5,000-6,000 m | 2,676 | 0.5% |
| 6,000-7,000 m | 1,526 | 0.3% |
| 7,000-8,000 m | 282 | 0.1% |
| 8,000-8,849 m | 27 | 0.0% |

512,507 of the 687,599 summits in the app's database carry an elevation tag. OpenStreetMap contributors, ODbL.

Well over half of the summits with a recorded elevation are below 1,000 m, the height many people would call a hill. Fewer than 2,000 rise above 6,000 m. Every one of them has a name somebody uses, which is the most practical test there is.

## Naming the one you're looking at

Whatever you call it, the harder question is usually which one it is. Our guide to [what mountain is this](https://mountainidentifier.org/guides/what-mountain-is-this) covers the methods. Mountain Identifier: Peaks labels summits of every size in its live view, hills included, as long as they're in OpenStreetMap and within 80 km; the live view is part of the Pro subscription.

### How tall does a hill have to be to be a mountain?

There's no agreed figure. Older rules used 1,000 ft (305 m), and some modern British usage uses 2,000 ft (610 m), but these are conventions. Names are local: there are features called hills that are far higher than places elsewhere called mountains.

### What is the tallest hill in the world?

Cavanal Hill in Oklahoma is often called the world's highest hill, at 1,999 ft, on the idea that 2,000 ft makes a mountain. It's a local claim, not an official title, since no authority defines the line.

### Is a peak the same as a mountain?

Not exactly. A peak is a high point; a mountain is the whole landform. A single mountain can have several peaks, such as a main summit and lower subsidiary tops along its ridges.

### Is a volcano a mountain?

Usually. A volcano is defined by how it formed, through eruptions, while mountain describes size and shape. Large volcanoes like Mount Fuji or Kilimanjaro are mountains by any measure; small cinder cones can be hill-sized.

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Peak data (c) OpenStreetMap contributors, licensed ODbL.

Mountain Identifier: Peaks is an iOS app by Patrick Tammaro. Free to download; identifying peaks is part of the Pro subscription. App Store: https://apps.apple.com/us/app/mountain-identifier-peaks/id6752865266