Pottawatomie County in northeastern Kansas is split between the Kansas River lowlands in the south and a much more dissected upland landscape farther north. Wamego and St. Marys sit along the US 24 corridor near the river, while Westmoreland, Onaga, and Olsburg occupy smaller inland settings among ridges and creek valleys. The western edge also follows the Tuttle Creek and Big Blue River system, giving the county a strongly water-shaped boundary. High-resolution map files are available for download in the section below.
This guide follows Wamego, St. Marys, Westmoreland, Onaga, and the surrounding roads and streams across an elevation range of roughly 278 to 476 meters. WebP previews are available for quick viewing, and the matching high-resolution JPG files can be downloaded together in one ZIP for printing, classroom work, or offline reference.
Table of Contents
US 24 links the largest southern communities along the Kansas River
US 24 is the clearest east–west road across the southern part of the county. It enters from the Manhattan side, passes St. George and Wamego, continues through Belvue, and reaches St. Marys near the eastern edge. At Wamego, K-99 turns north toward Westmoreland and the interior uplands, making the city the most useful road junction on the map.
The City of Wamego describes the community at the junction of US 24 and K-99 and notes that it lies on the banks of the Kansas River. That relationship is easy to see on the supplied map: highway, rail corridor, town, and river are packed into the same narrow southern lowland.
Northern travel uses a different pattern. K-16 crosses the Onaga and Wheaton area, K-13 serves the western side near Olsburg, and K-63 reaches the eastern side above St. Marys. The northern towns are much farther apart than the communities along US 24, which gives the county two very different settlement patterns.
Wamego and St. Marys dominate the city index, but Westmoreland is the county seat
The ranked city panel lists Wamego at 4,386 and St. Marys at 2,788. St. George follows at 1,039, while Onaga is 727, Westmoreland 703, and Olsburg 269. These are map index values rather than current official population estimates, but they explain the large difference in marker size between the southern cities and the smaller inland communities.
Location matters as much as the ranking. Wamego, St. George, and St. Marys belong to the Kansas River and US 24 corridor, while Onaga, Westmoreland, and Olsburg sit in hillier interior terrain. Pottawatomie County’s official offices are in Westmoreland, so the administrative center is different from the largest population marker.
That split is useful when reading the rest of the maps. The southern corridor is more urban and transportation-oriented, while the northern half is defined by smaller towns, rolling uplands, and dense creek networks.
The Kansas River and Tuttle Creek system frame the county’s lowest terrain
The Kansas River follows the southern edge of the county and forms the broadest continuous lowland on the water map. Wamego and St. Marys lie close to this corridor, and numerous small streams descend from the interior hills before reaching the river.
Along the western edge, the Tuttle Creek Lake and Big Blue River system forms a long irregular water boundary. Spring Creek and Carnahan Creek cut down through the western uplands, while Pleasant Run Creek and Rock Creek drain the central-western interior. The shoreline and river edge create a much more complex boundary than a simple straight county line.
The central and eastern county contains another dense group of streams. Indian Creek, Gold Creek, Vermillion Creek, Mill Creek, Lost Creek, and smaller tributaries cut long valleys through the uplands. Watershed Lake appears in the eastern part of the map as a smaller local water feature.
This water image is intended for geographic reference rather than floodplain, navigation, water-quality, parcel, or legal-access decisions. Water level and flow can change, so current agency information should be used whenever access or safety conditions matter.
Relief from 278 to 476 meters rises sharply away from the Kansas River
The elevation surface ranges from about 278 to 476 meters, with a mean near 371 meters. The Kansas River corridor is the broadest dark-green lowland, while brown and tan uplands become much more extensive toward the north and northwest. Nearly 200 meters of local relief separates the lowest river terrain from the highest hills.
The western side is especially rugged because low water along the Tuttle Creek system lies directly beside steep, narrow uplands. Pleasant Run Creek and Rock Creek cut deep green corridors through central hills, and Indian Creek and Vermillion Creek do the same farther east. Rather than one smooth slope, the county is a repeating pattern of ridges and stream valleys.
Wamego and St. Marys sit close to low river terrain, while the route from Westmoreland toward Onaga crosses much higher rolling country. Olsburg also lies near a sharp transition where the western reservoir and river system meets elevated ground.
The elevation surface is generalized for county-scale comparison. It is not survey-grade or engineering-grade measurement and should not be used for parcel elevations, construction grades, drainage design, or legal boundary work.
Westmoreland is the administrative center in the middle of the uplands
Pottawatomie County’s official website lists its county offices at 207 North 1st Street in Westmoreland. That makes Westmoreland the administrative center even though Wamego and St. Marys rank much higher on the supplied city index. On the map, Westmoreland also works as a useful midpoint between the southern river corridor and the smaller northern communities.
A county-specific outdoor feature lies nearby. Kansas Department of Wildlife and Parks places Pottawatomie State Fishing Lake No. 1 about five miles north of Westmoreland, or two miles south of Blaine, on K-99. The 24-acre lake sits within rolling terrain and provides a useful real-world reference for the central uplands shown on the map.
Wamego shows how closely the city, highway, and river are packed together
The City of Wamego describes the community at the intersection of US 24 and K-99, directly along the Kansas River. The city’s geography is unusually clear on the map because the river, highway, rail line, and built-up area all occupy the same narrow southern corridor.
Wamego’s Riverfront Park provides an even more specific example. The city places the park immediately west of the Lincoln Avenue K-99 bridge over the Kansas River. That location makes the relationship between the town and the river more than a broad regional observation—it is visible at the street and bridge level.
Driving north from Wamego reveals the county’s strongest elevation change
Following K-99 north from Wamego toward Westmoreland leaves the broad Kansas River lowland and quickly enters terrain cut by many small streams. Continuing toward the Onaga side brings the route into still higher hills, with narrow creek valleys repeatedly interrupting the upland surface.
The contrast with the St. Marys direction is strong. US 24 toward the southeast stays much closer to the Kansas River lowland, while the northern interior climbs away from the river and becomes more dissected. Comparing those two corridors explains much of Pottawatomie County’s geography without reducing it to a checklist of map types.
For posters, classroom prints, or presentation slides, use the original JPG files in the download archive rather than enlarging the web previews. Small road labels, creek names, town text, and the elevation legend remain clearer at the higher resolution.
Frequently Asked Questions
Which city is largest on the supplied city index?
Wamego ranks first at 4,386, followed by St. Marys at 2,788. St. George is 1,039, Onaga 727, Westmoreland 703, and Olsburg 269. These are map index values rather than current official population estimates.
How different are the Kansas River lowlands from the northern hills?
The elevation range is about 278 to 476 meters. The Kansas River corridor is the broadest low area, while the Westmoreland-to-Onaga and northwestern parts of the county contain much higher rolling hills.
Can the 278–476 meter elevation image be used for surveying?
No. It is a generalized county-scale terrain image for comparing river lowlands with higher uplands. Parcel elevations, engineering grades, drainage design, and legal boundary work require more precise official data and, where needed, professional surveying.
Map File Information
The archive contains the Pottawatomie County, Kansas general county map, city map, terrain-and-water map, and elevation map as original high-resolution JPG files.
- Included Files: Use only the versions confirmed in the article and supplied images
- File Type: Use the confirmed download contents
- Intended Use: Printing, education, presentations, and map-based projects
Related Maps
Sources and references
- Pottawatomie County, Kansas official website — county government and Westmoreland office information
- City of Wamego: About Wamego — US 24, K-99, the Kansas River, and local geography
- Kansas Department of Wildlife and Parks: Pottawatomie State Fishing Lake No. 1 — lake location north of Westmoreland and local recreation context
- Kansas Department of Wildlife and Parks: Tuttle Creek State Park — Tuttle Creek Reservoir and western water landscape context
- U.S. Census Bureau TIGER/Line Shapefiles — county boundary and geographic reference data
- USGS 3D Elevation Program — elevation and terrain reference data
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.
