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GNIS Domestic Names Feature Classes

The names and definitions of all feature classes represented in the BGN's Geographic Names Information System (GNIS) for domestic names.

The table below shows all feature classes catalogued in the GNIS, their definitions, and examples of generic names associated with the feature class in alphabetical order.
Feature Class Description
Arch Natural arch-like opening in a rock mass (bridge, natural bridge, sea arch).
Area Any one of several areally extensive natural features not included in other categories (badlands,
barren, delta, fan, garden).
Arroyo Colloquial usage in southwestern United States. The valley of an ephemeral stream with a flat floor
and steep banks or the ephemeral stream flowing through a valley with a flat floor and steep banks,
either hydrographic or hypsographic (draw, wash, gully).
Bar Natural accumulation of sand, gravel, or alluvium forming an underwater or exposed embankment
(ledge, reef, sandbar, shoal, spit).
Basin Natural depression or relatively low area enclosed by higher land (amphitheater, cirque, pit, sink).
Bay Indentation of a coastline or shoreline enclosing a part of a body of water; a body of water partly
surrounded by land (arm, bight, cove, estuary, gulf, inlet, sound).
Beach The sloping shore along a body of water that is washed by waves or tides and is usually covered by
sand or gravel (coast, shore, strand).
Bench Area of level to gently sloping land on the flank of an elevation such as a hill, ridge, or mountain
where the slope of the land rises on one side and descends on the opposite side (first bottom,
flood-plain step, level, terrace, tread).
Bend Curve in the course of a stream and (or) the land within the curve; a curve in a linear body of
water (bottom, loop, meander).
Canal Waterway, primarily manmade, used by watercraft or for drainage, irrigation, mining, or
waterpower (ditch, lateral, sluice).
Cape Projection of land extending into a body of water (lea, neck, peninsula, point).
Census A statistical area delineated locally specifically for the tabulation of Census Bureau data (census
designated place, census county division, unorganized territory, various types of
American Indian/Alaska Native statistical areas). Distinct from Civil and Populated Place.
Channel Linear deep part of a body of water through which the main volume of water flows and is frequently
used as a route for watercraft (passage, reach, strait, thoroughfare, throughfare).
Not a Stream or Valley.
Civil A political division formed for administrative purposes (borough, county, incorporated place,
municipio, parish, town, township). Distinct from Census and Populated Place.
Cliff Very steep or vertical slope on one side (bluff, crag, escarpment, head, headland, nose, palisades,
precipice, promontory, rim, rimrock, scarp).
Crater Circular-shaped depression at the summit of a volcanic cone or one on the surface of the land caused
by the impact of a meteorite; a manmade depression caused by an explosion
(bowl, caldera, lua, maar).
Crossing A place at which a river or stream may be crossed (landing, ferry, ford).
Falls Perpendicular or very steep fall of water in the course of a stream (cascade, cataract, waterfall).
Flat Relative level area within a region of greater relief (clearing, glade, pan, park, playa lake,
salina, upland)
Gap Low point or opening between hills or mountains or in a ridge or mountain range (col, notch, pass,
saddle, water gap, wind gap).
Glacier Body or stream of ice moving outward and downslope from an area of accumulation; an area of
relatively permanent snow or ice on the top or side of a mountain or mountainous area (icefield,
ice patch, snow patch).
Gut Relatively small coastal waterway connecting larger bodies of water or other waterways
(creek, inlet, slough).
Island Area of dry or relatively dry land surrounded by water or low wetland (archipelago, atoll, cay,
hammock, hummock, isla, isle, key, moku, rock).
Isthmus Narrow section of land in a body of water connecting two larger land areas.
Lake Natural body of inland water (backwater, lac, lagoon, laguna, oxbow, pond, pool, resaca,
tank, tarn, waterhole).
Lava Formations resulting from the consolidation of molten rock on the surface of the Earth (kepula,
lava flow, māwae, traps).
Levee Natural or manmade embankment flanking a stream (bank, berm).
Military Place or facility used for various aspects of or relating to military activity.
Pillar Vertical, standing, often spire-shaped, natural rock formation (chimney, hoodoo, monument,
pinnacle, pōhaku, rock tower).
Plain A region of general uniform slope, comparatively level and of considerable extent; can refer to the
flat area of a large mesa (desert, grassland, highland, kula, plateau, savanna).
Populated Place Place or area with clustered or scattered buildings and a permanent human population (city,
settlement, town, village). A populated place is usually not incorporated and by definition
has no legal boundaries. However, a populated place may have a corresponding "civil" record,
the legal boundaries of which may or may not coincide with the perceived populated place.
Distinct from Census and Civil classes.
Range A single mass of hills or mountains; a complex, interconnected series of mountain ranges having
a well-defined longitudinal trend (cordillera, mountain belt, sierra).
Rapids Fast-flowing section of a stream with turbulent flow, often shallow and with exposed rock or
boulders, wheredischarge is mostly influenced by velocity rather than width and depth
(dalles, riffle, ripple).
Reservoir Artificially impounded body of water (lake, tank).
Ridge Elevation with a narrow, elongated crest that can be part of a hill or mountain (arête, crest, chenier,
cuesta, divide, esker, hogback, mogote, lae, ridge, spur).
Sea Large body of salt water (gulf, ocean).
Slope A gently inclined part of the Earth's surface (grade, pitch).
Spring Place where underground water flows naturally to the surface of the Earth (seep).
Stream Linear body of water flowing on the Earth's surface (anabranch, awāwa, bayou, branch, brook, creek,
distributary, fork, kill, pup, rio, river, run, slough)
Summit Prominent elevation rising above the surrounding level of the Earth's surface; does not include
pillars, ridges, or ranges; can occur as a single isolated mass or in a group (ahu, ballon, berg,
bald, butte, cerro, colina, cone, cumbre, dome, head, hill, horn, knob, knoll, mauna, mesa,
mesita, mound, mount, mountain, peak, puʻu, rock, sugarloaf, table, volcano).
Swamp Poorly drained wetland, fresh or saltwater, wooded or grassy, possibly covered with open water
(bog, cienega, everglades, fen, marais, marsh, pocosin, slough).
Valley Linear depression in the Earth's surface that generally slopes from one end to the other (barranca,
canyon, chasm, cirque, cove, coulee, draw, fjord, glen, gorge, gulch, gulf, gully, hollow, ravine).
Woods Small area covered with a dense growth of trees; does not include an area of trees under the
administration of a political agency.

Note: Until 2021, the Geographic Names Information System also contained administrative and manmade feature classes such as Airport, Bridge, Building, Cemetery, Church, Dam, Forest, Harbor, Hospital, Mine, Oilfield, Park, Post Office, Reserve, School, Tower, Trail, Tunnel, and Well. These features are no longer in GNIS. Please see the Download GNIS Data page to learn how to access legacy data that utilizes these feature classes.