What Does “Coulee” Mean? A Practical Guide to Passes, Ridges, Hollows, Approaches, and Other Geographic Terms

Have you ever read a trail description that mentions crossing a saddle, following a draw, or approaching a mountain through a coulee?

You may understand the general idea from context, but outdoor writers, mapmakers, weather forecasters, and local residents use a surprising number of words to describe the shape of the land.

Some of these terms are nearly interchangeable. Others have specific meanings. A few mean slightly different things depending on where you are in the country.

Here is a practical guide to geographic terms you may encounter while hiking, camping, driving through unfamiliar terrain, checking an outdoor forecast, or exploring a new part of the country.

Mountain Pass

A mountain pass is a lower point or route through a mountain range or area of high terrain.

Instead of traveling directly over the highest part of a mountain, roads, trails, railroads, and historic migration routes often follow a pass. It is usually the most practical place to cross from one side of a mountain range to the other.

A pass can still be quite high in elevation. It is simply lower than the surrounding peaks and ridges.

Mountain passes can also have noticeably different weather than nearby lower elevations. Snow, strong winds, fog, ice, and rapidly changing conditions are common concerns.

Think of it as: A doorway through the mountains.

Saddle

A saddle is a low point between two higher areas, often between two peaks along the same ridge.

Imagine the shape of a riding saddle. The front and back rise, while the middle dips lower. The landform looks similar when viewed from the side.

Hiking routes frequently cross saddles because they offer an easier way to move between valleys, ridges, or peaks. A saddle may also be called a col, particularly in mountaineering descriptions.

Think of it as: A dip between two high points.

Gap

A gap is an opening or low point through hills, mountains, or a ridge.

In everyday outdoor use, a gap may be very similar to a pass. The difference is often regional naming rather than a strict geographic distinction.

Gaps are especially common in place names in the Appalachian Mountains. Cumberland Gap, for example, became an important route through the mountains because it provided a natural opening through otherwise difficult terrain.

Think of it as: A break in a natural wall of higher land.

Notch

A notch is another word for a narrow gap or pass through mountains or a ridge.

The word is especially common in New England. A notch may contain a hiking trail, highway, river, or combination of all three.

Compared with the broad idea of a mountain pass, “notch” often suggests a more sharply defined opening cut into the surrounding terrain.

Think of it as: A V-shaped cut in a ridge or mountain range.

Coulee

A coulee is generally a valley, ravine, drainage channel, or long depression in the land.

This is one of the more confusing terms because its exact meaning changes by region.

In Wisconsin, Minnesota, and parts of the Upper Midwest, a coulee often refers to a narrow valley between steep hills or bluffs. The term is closely associated with the Driftless Area, where streams and erosion have carved deep valleys into the landscape.

In parts of the western United States and Canada, a coulee may refer to a dry or occasionally flowing channel. Some western coulees are enormous channels created by ancient floods rather than ordinary stream erosion.

Water may flow through a coulee year-round, seasonally, only after heavy rain, or not at all today.

Think of it as: A valley or channel where water flows, or once flowed.

Draw

A draw is a small natural drainage or shallow valley between two areas of higher ground.

Draws often carry water downhill during rain or snowmelt, although they may remain dry most of the year.

On a topographic map, a draw appears as contour lines forming a V shape that points toward higher elevation. Water would generally flow in the opposite direction, out through the open end of the V.

Hikers may follow a draw because it provides a gradual route uphill. However, narrow draws can also collect runoff and may be dangerous during flash floods.

Think of it as: A small drainage groove in the landscape.

Gully

A gully is a channel cut into the ground by running water.

It is generally smaller than a canyon but deeper and more sharply eroded than a shallow draw. Gullies may form on hillsides, along trails, in farm fields, or below areas where water becomes concentrated.

A gully can be difficult to cross and may become slippery, unstable, or filled with fast-moving water during heavy rain.

Think of it as: A deep erosion channel.

Ravine

A ravine is a narrow, steep-sided valley, usually shaped by flowing water.

Ravines are typically larger and more established than gullies but smaller than major canyons. They may contain streams, waterfalls, exposed rock, dense vegetation, and cooler conditions than the surrounding uplands.

The exact dividing line between a ravine, gorge, and canyon is not consistent. Local naming and tradition often matter as much as size.

Think of it as: A narrow valley with steep sides.

Gorge

A gorge is a deep, narrow valley with steep rocky walls, usually carved by a river or stream.

Gorges commonly form where water cuts downward through resistant rock. They may contain rapids, waterfalls, cliffs, and very limited routes in or out.

Although “gorge” and “canyon” are sometimes used interchangeably, gorge often implies a particularly narrow and steep-sided feature.

Think of it as: A deep, narrow river-cut passage.

Canyon

A canyon is a deep valley with steep sides, most commonly carved over time by a river.

Canyons vary enormously in size. Some are small enough to hike through in an afternoon, while others form vast systems extending for hundreds of miles.

Desert canyons require special attention because rainfall many miles away can send water rushing through narrow channels. Clear skies directly overhead do not always mean there is no flash-flood risk.

Think of it as: A large, deeply cut valley.

Hollow or Holler

A hollow is a small, sheltered valley, particularly in the Appalachian region.

In local speech, especially in parts of Appalachia, “hollow” is often pronounced and written as holler.

Hollows frequently contain streams, roads, homes, and small communities. Because they are enclosed by higher land, they may receive less direct sunlight and can trap cool air, fog, or smoke.

Think of it as: A small valley tucked between hills.

Valley

A valley is a lower area between hills or mountains.

Many valleys contain rivers or streams because water naturally moves toward lower ground. River-cut valleys are commonly V-shaped, while valleys shaped by glaciers are often broader and more U-shaped.

Valleys frequently become travel corridors because they offer easier terrain than the surrounding slopes. Roads, railroads, towns, and farms often follow them.

Think of it as: Low land between higher land.

Basin

A basin is an area of land that sits lower than the surrounding terrain.

Water may drain into the basin and then exit through a river, or it may collect with no natural outlet. The word is also used in the term drainage basin, meaning all the land that drains toward the same river, lake, or other body of water.

A basin can be small and local or cover an enormous region.

Think of it as: A bowl-shaped area in the landscape.

Ridge

A ridge is a long, narrow area of elevated ground.

Ridges often connect peaks or separate neighboring valleys and drainage systems. Hiking along a ridge can provide excellent views, but it may also mean increased exposure to wind, lightning, sun, and changing weather.

Water that falls on opposite sides of a ridge may flow toward completely different streams or rivers.

Think of it as: The long spine of a hill or mountain.

Ridgeline

A ridgeline is the uppermost line along a ridge.

When someone says a trail “follows the ridgeline,” it generally means the route stays near the crest rather than dropping far down either side.

Ridgelines are easy to identify from a distance, especially when they form the visible outline of mountains against the sky.

Think of it as: The top edge of a ridge.

Spur

A spur is a smaller ridge that extends away from a main ridge or mountain.

It is similar to a branch extending from the trunk of a tree. Trails sometimes follow spurs because they provide a natural route from a valley to a higher ridgeline.

On a topographic map, a spur often appears as contour lines forming a U or V shape pointing downhill.

Think of it as: A side branch of a larger ridge.

Divide

A divide is an elevated boundary separating two drainage areas.

Rain falling on one side flows toward one river system, while rain falling on the other side flows somewhere else. A divide may follow a dramatic mountain ridge, but it can also cross land that appears relatively gentle.

The Continental Divide is the best-known American example, separating watersheds that ultimately drain toward different sides of the continent.

Think of it as: The line separating where water goes.

Bluff

A bluff is a high, steep slope or cliff, often overlooking a river, lake, valley, or plain.

Bluffs are prominent throughout the Upper Mississippi River region and the Driftless Area. They may be topped with forests, prairie, overlooks, or hiking trails.

A bluff does not need to be a sheer vertical cliff. It may include steep wooded slopes and exposed rock faces.

Think of it as: High, steep land overlooking a lower area.

Escarpment

An escarpment is a long, steep slope or cliff separating two areas of relatively level land at different elevations.

Unlike a single isolated bluff, an escarpment may extend across a large region. It can be created by erosion, faulting, or differences in the resistance of rock layers.

The Niagara Escarpment, which extends far beyond Niagara Falls, is one well-known example.

Think of it as: A long step in the landscape.

Plateau

A plateau is a broad area of elevated land that is relatively level on top.

Plateaus can contain valleys, rivers, canyons, and mountains, so they are not always perfectly flat. What matters is that the broader region is elevated above the surrounding land.

A plateau may end in cliffs or steep slopes and can cover hundreds or thousands of square miles.

Think of it as: A large, high table of land.

Mesa

A mesa is an isolated, flat-topped area of high ground with steep sides.

The word comes from the Spanish word for “table.” Mesas are especially common in dry regions where erosion removes softer surrounding material while harder rock protects the top.

Mesas are smaller than plateaus but larger than buttes.

Think of it as: A large, flat-topped natural table.

Butte

A butte is an isolated hill with steep sides and a relatively small, often flat top.

Buttes form through erosion and are generally considered smaller than mesas. The distinction is not based on one universally accepted measurement, so the name may depend partly on local usage.

Think of it as: A small mesa standing by itself.

Peak and Summit

A peak is a pointed or prominent high point of a mountain. A summit is the highest point of a mountain or hill.

In ordinary conversation, the two words are often used interchangeably. Technically, a mountain may contain several peaks, but only one point is its highest summit.

“Summit” can also describe the act of reaching the top, as in, “We summited the mountain.”

Think of it as: The peak is a prominent top; the summit is the highest point.

Foothills

Foothills are lower hills located at the base of a mountain range.

They form a transition between flatter land and higher mountains. Although foothills sound mild compared with major peaks, they can still contain steep trails, rugged terrain, and significant elevation changes.

Think of it as: The smaller hills leading toward the mountains.

Approach

An approach is not a landform. It is the route, journey, or section of terrain used to reach the main objective.

A climbing guide may describe a “two-mile approach” before the actual climb begins. A hiking route might include an approach trail leading to a mountain, canyon, waterfall, or remote campsite.

The approach can involve roads, trails, river crossings, scrambling, snow travel, or off-trail navigation. A “long approach” may mean the main attraction is much farther from the trailhead than it first appears.

Weather forecasts also sometimes refer to conditions “on the western approaches” to a pass, lake, mountain, or coastal area. In that context, approaches are the surrounding routes or areas leading toward the named feature.

Think of it as: The part you travel before reaching the main event.

Trailhead

A trailhead is the official or commonly used starting point of a trail.

It may include a parking area, sign, map, restroom, registration station, or information board. Some remote trailheads are little more than a place where a path leaves a road.

Reaching the trailhead can sometimes be an adventure of its own, particularly when access requires rough roads or seasonal river crossings.

Think of it as: The front door of the trail.

Switchback

A switchback is a sharp turn in a trail or road that allows it to climb or descend a steep slope gradually.

Rather than heading straight uphill, the route travels back and forth across the slope. This makes the grade more manageable and helps reduce erosion.

Cutting directly between switchbacks damages vegetation and creates channels where water can erode the trail.

Think of it as: A zigzag used to gain or lose elevation.

Traverse

To traverse means to travel across a slope, mountain face, ridge, glacier, or other area rather than moving directly up or down it.

A trail description may refer to a “long traverse across the hillside.” Climbers may also traverse from one route, peak, or section of rock to another.

A traverse can feel easier because it reduces the steepness of the climb, but it may involve exposed slopes or difficult footing.

Think of it as: Moving sideways across the terrain.

Scramble

A scramble is a section of travel that falls somewhere between ordinary hiking and technical rock climbing.

You may need to use your hands for balance or to climb over rocks, but specialized climbing equipment is not always required.

Difficulty varies widely. A casual description of a “short scramble” may still feel intimidating to someone uncomfortable with heights or exposure.

Think of it as: Hiking that occasionally requires your hands.

Exposure

In hiking and climbing, exposure refers to the risk or feeling created by a steep drop, open slope, cliff edge, or lack of protection from the terrain.

A narrow trail may not be technically difficult, but it can feel much harder when a large drop is immediately beside it.

Exposure can also describe vulnerability to weather. An exposed ridge provides little shelter from wind, lightning, sun, or blowing snow.

Think of it as: How open, unprotected, or close to a drop the route feels.

Drainage and Watershed

A drainage is an area or channel through which water flows downhill. Depending on the context, it may refer to a small ravine, a creek valley, or an entire river system.

A watershed is all the land that drains water toward the same outlet, such as a stream, river, lake, or ocean.

Ridges and divides form the boundaries between neighboring watersheds.

Think of it as: A drainage is where water travels; a watershed is the land collecting it.

Why These Terms Are Not Always Precise

Geographic words developed through local history, different languages, mapping traditions, geology, and everyday speech.

A feature called a hollow in Kentucky might be called a coulee in Wisconsin, a draw in Montana, or a small valley somewhere else. A pass, gap, saddle, notch, and col can all describe related features, but one name may be much more common in a particular region.

Size does not always settle the question either. There is no universal measurement at which a ravine officially becomes a canyon or a mesa becomes a plateau.

The practical goal is not to memorize a rigid definition for every term. It is to recognize what the word is telling you about the terrain.

Use the Words as Clues

Geographic terms provide useful clues before you arrive.

• A ridge may be windy and exposed.
• A draw, gully, or coulee may collect water.
• A pass may have rapidly changing mountain weather.
• A hollow may be shaded, damp, and cooler than nearby hills.
• A bluff may offer a great view but involve steep slopes or cliff edges.
• A long approach means you need to account for additional distance before the main activity begins.
• An exposed ridgeline may be a poor place to be during a thunderstorm.

Once you begin recognizing these words, trail descriptions and topographic maps become much easier to visualize. You can start forming a picture of the landscape before you ever leave home.

That can help you choose the right route, understand a weather forecast, estimate the effort involved, and arrive better prepared for what is actually outside.