Gilliam County stretches south from the Columbia River into the dry interior of north-central Oregon. Arlington sits at the river on the county’s northern edge, while Condon lies well inland and farther south. Lonerock appears near the southeastern part of the county, separated from both by broad areas of rolling and dissected terrain. The maps on this page make that long north-to-south layout easy to see without reducing the county to a simple rectangle.
The page includes a county-and-roads map, a city-connections map, a terrain-and-water map, and an elevation map. High-resolution JPG versions of all four are available together in the download ZIP. The web images are useful for quick reference, while the larger originals are better when you want to zoom in on road numbers, creek labels, or the irregular western boundary for print, classwork, or a presentation.
Table of Contents
A long county linking Arlington on the Columbia with Condon inland
The general county map gives Gilliam County a distinctive shape. The northern section widens along the Columbia River, then the county extends much farther south through an interior of small streams and sparse settlements. Arlington is the obvious northern reference point, Condon is the main inland center, Mayville appears south of Condon, and Lonerock occupies the southeastern side. Because these places are spread across a large area, the road network is more informative than a simple list of town names.
Along the Columbia, shields for 30 and 84 appear on the main east-west corridor. From Arlington, a major route runs south toward Condon through the middle of the county. Near Condon, Oregon 206 heads east, while Oregon 19 continues south toward Mayville and the Wheeler County line. Oregon 74 appears along the northeastern side. Together these roads show how movement is organized around a river corridor in the north and longer inland routes through the center and south.
The western county line is especially irregular. It winds through a series of bends rather than following one long straight survey line, with Wasco County to the west and Sherman County near the northwest. The eastern side has longer straight segments, but the boundary steps inward and outward in the southeast. That shape matters when checking whether a rural road, creek, or named place falls inside Gilliam County, and it is one reason the boundary map is more useful than relying only on a regional road map.
Arlington and Condon also represent two very different settings. Arlington is close to the Columbia River and the major transport corridor along it. Condon is inland, at a noticeably higher elevation, and serves as the county seat. The Oregon Judicial Department notes that Gilliam County was created in 1885; the county seat was first at Alkali, the present-day Arlington area, before moving to Condon in 1890. The map makes the physical separation between those historic administrative centers immediately apparent.
Condon is a useful road reference because several directions become clear from there. The route to Arlington runs north, Oregon 206 extends east, and Oregon 19 continues south. Lonerock, by contrast, is not simply the next settlement down the same road. It lies farther southeast in a landscape where creeks, canyons, and uplands occupy more of the map than named towns. That difference helps explain why a county map that includes both roads and terrain context is more informative here than a plain political outline.
Straight-line spacing from Arlington to Condon and Lonerock
The city-connections map strips away much of the road detail and focuses on three reference places. Arlington is marked as the hub in the north. Condon is shown about 34 miles away, while Lonerock is about 46 miles from Arlington. These are straight-line distances between mapped points, not driving distances. Actual road travel can be longer because routes must follow the available highways and the shape of the terrain rather than a direct line across the county.
This simplified view emphasizes the county’s north-south scale. Arlington occupies the low northern edge beside the Columbia. Condon is much farther inland, and Lonerock sits beyond it to the southeast. The map is useful when the question is simply where the main named settlements are in relation to one another. It is less suitable for estimating trip times, because a straight line does not show road curvature, grades, intersections, or seasonal travel conditions.
Used beside the county map, the city-connections graphic becomes more informative. The connection from Arlington to Condon looks simple as a point-to-point comparison, but the general map shows the road system that actually links the two areas. Lonerock appears close to the southern edge and away from the main Arlington–Condon axis. This combination helps separate two different questions: how far apart places are in geographic space, and how people move between them on the road network.
Gilliam County’s broad rural spaces are also part of the context. The Oregon Judicial Department describes the county as part of the Columbia Basin wheat area, with wheat, barley, cattle, and more recently wind energy playing important roles in the local economy. Those activities are not mapped directly here, so the images should not be treated as land-use maps. Still, the small number of labeled settlements and the large areas between them are consistent with a county where rural land occupies most of the space.
Columbia River lowlands and a network of interior creeks
The terrain-and-water map is dominated in the north by the Columbia River. It follows the county’s upper edge as a broad blue corridor, and Arlington is located close to it on the other maps. South of the river, the drainage pattern becomes much finer. Dozens of short channels and canyon bottoms cut into the interior, producing a landscape that is much more dissected than the pale background of the road map might suggest.
Rock Creek is one of the most useful interior reference streams, running through the eastern part of the county and receiving smaller branches. The map also labels East Fork Thirtymile Creek, Lone Rock Creek, Willow Creek, Hay Creek, Spanish Gulch, Ferry Canyon, and other smaller drainages. These names show that the county is divided by many local valleys rather than by a single river running down the middle. Around Lonerock, the creek network is especially useful for understanding how the southeastern settlement fits into the surrounding terrain.
Rock Creek provides a helpful line through the eastern interior. Smaller tributaries join it from nearby slopes, while other drainages remain separate farther west. East Fork Thirtymile Creek and Lone Rock Creek help orient the southeastern section, where the terrain is broken into narrow valleys and ridges. When this map is compared with the road map, it becomes easier to see why direct-looking locations may still require winding travel: roads must cross or follow a landscape shaped by repeated gullies and creek valleys.
The western side of Gilliam County has strongly cut terrain near the irregular county boundary. Labels such as Hay Creek, Ferry Canyon, and Spanish Gulch sit among shaded ridges and narrow channels. By contrast, the area immediately south of the Columbia River is lower and visually more open. This difference between river-edge lowland and interior upland is one of the county’s strongest geographic themes, and the elevation map makes the same transition even clearer through color.
This is a reference map for waterways and terrain, not a flood-risk or navigation product. A blue stream line does not mean that flow is constant through every season, nor does it identify legal access, parcel boundaries, bridge conditions, or current water levels. For those questions, use current information from the appropriate state or federal agency. The map is best used to locate named waterways and to understand how drainage lines fit among the county’s ridges and valleys.
Elevation rises sharply away from the Columbia River
The elevation map makes the county’s vertical range easy to recognize. Its legend shows an actual range of about 81 meters to 1,306 meters, with a mean near 598 meters. Dark green marks the lowest terrain along the Columbia River and some major valleys. Farther south, green gives way to lighter green, yellow, orange, and brown across higher ground. The greatest elevations appear in the southern and southeastern parts of the county, where ridges are cut by narrow drainage corridors.
Arlington’s setting is clearly part of the low northern zone. Moving south toward Condon, the terrain climbs and the color palette shifts away from the deep greens near the river. South and southwest of Condon, higher surfaces are interrupted by green strips where creeks and canyons cut into the upland. The result is not a smooth ramp from low to high. Instead, Gilliam County has broad elevated areas separated by many local valleys, which is exactly what the water map suggests.
The Lonerock and Rock Creek side of the county shows the same relationship in a different form. Higher ridges occupy much of the southeast, while lower colors follow creek valleys through them. Comparing the water and elevation maps is useful because each explains the other: stream lines occupy many of the lower corridors, while the surrounding ridges account for the strong relief shading. This paired view is more useful than relying on a single elevation number for the county as a whole.
The elevation surface is generalized for county-scale reference. It should not be used as a survey-grade measurement for an individual road, building site, drainage design, or parcel. Engineering and construction work require original elevation data and field measurements at an appropriate scale. For classroom use, regional orientation, travel planning, or a printed county overview, however, the map clearly communicates the large change from the Columbia River lowlands to the southern uplands.
Choosing the most useful Gilliam County map for the task
Start with the general county map when you need boundaries, roads, and named places together. It is the best choice for locating Arlington, Condon, Mayville, and Lonerock while also seeing the route numbers and neighboring counties. The northern Columbia corridor and the road running south toward Condon are especially clear. For a travel handout or an introductory slide, this map provides enough context that a reader can understand the county without needing another regional map first.
Use the city-connections map when the main question is how the principal labeled settlements are spaced. Its limited detail is a benefit when presenting to an audience that does not need every road or stream. Just remember that the 34-mile and 46-mile figures are straight-line distances from Arlington, so they should not be copied into a driving itinerary as road mileage. Pairing this map with the general map is a simple way to show geographic spacing first and actual road context second.
The terrain-and-water map is the stronger choice for explaining the Columbia River, Rock Creek, Thirtymile Creek branches, and the many smaller canyons that divide the interior. The elevation map is better when the goal is to show how dramatically the land rises away from the river. Used together, they explain why a county that looks fairly open on a road map can contain deep drainage cuts and substantial local relief across its southern half.
For printing or detailed viewing, the original JPG files provide more room to zoom than the web previews. Each source image is approximately 3,638 by 2,572 pixels. You can use the maps separately rather than forcing all four into one page: the roads map and city map work well for settlement-oriented material, while the water and elevation maps make a stronger pair for physical geography. Selecting only the maps that answer the specific question usually produces a clearer handout or presentation.
Gilliam County’s geography is defined by contrast. The Columbia River anchors a low northern edge, Arlington and Condon sit in different parts of the county, and the southern interior rises into much higher, deeply cut terrain. Looking at roads, settlement spacing, drainage, and elevation separately makes those differences easier to understand. The four supplied maps cover the same county from complementary angles, so the best choice depends on whether you need location, connections, waterways, or relief.
Frequently Asked Questions
Which map is best for comparing Arlington and Condon?
The general county map is the best starting point because it shows both places with the road network and county boundary. Arlington is on the Columbia River in the north, while Condon is far inland to the south. The city-connections map is useful as a second view because it gives a straight-line comparison between the two, but its 34-mile figure is not driving mileage.
What are the main waterways shown in Gilliam County?
The Columbia River is the largest and most obvious feature along the northern edge. Inland, Rock Creek, branches of Thirtymile Creek, Willow Creek, Hay Creek, Lone Rock Creek, and other smaller drainages cut through the uplands. The water map is meant for geographic reference and should not be used as a flood map, a source of current streamflow, or a statement about legal access.
Can the elevation range of 81–1,306 meters be used for surveying?
No. The elevation map is a generalized county-scale surface intended to show broad relief, especially the contrast between the low Columbia River edge and the higher southern uplands. Surveying, engineering, construction, or parcel-level elevation work should rely on original elevation data and professional measurements at the required scale.
Map File Information
The download ZIP contains high-resolution JPG originals of the Gilliam County roads-and-boundary map, city-connections map, terrain-and-water map, and elevation map.
- File Type: JPG
Related Maps
Sources and reference links
For county boundaries and geographic reference, see the U.S. Census Bureau TIGER/Line resources. Waterway information can be checked against USGS National Hydrography, and elevation data are available through the USGS 3D Elevation Program. Background on the county seat and Gilliam County history is available from the Oregon Judicial Department’s Gilliam County page.
Green Map creates custom-edited map images using open geographic data sources such as geoBoundaries, Natural Earth, OpenStreetMap, and government open data. These maps are edited visual materials, not raw data files, and are provided for education, documents, presentations, and graphic reference.
