Lamar County is in the Historic Heartland travel region of Georgia. Its county seat is Barnesville, and the U.S. Census Bureau estimates the county had 20,690 residents in 2024, up from 18,502 in 2020. It covers about 184 square miles of land and was created in 1920.
- County seatBarnesville
- Population (2024 estimate)20,690
- Land area184 square miles
- Created1920
- Travel regionHistoric Heartland
Print it: download the printable Lamar County map (PDF), sized for standard letter paper (8.5 by 11 inches, portrait). Choose “actual size” or “fit to page” when you print.
Cities and Towns in Lamar County
Lamar County has 3 incorporated cities and towns. Populations are U.S. Census Bureau estimates for July 1, 2024, for the whole city, including any part in a neighboring county.
| City or town | 2024 population | Note |
|---|---|---|
| Barnesville (county seat) | 6,343 | |
| Milner | 807 | |
| Aldora | 189 |
Highways
Interstates and U.S. highways come from Census road data; state route numbers come from the Georgia Department of Transportation’s road inventory. In Georgia most U.S. highways also carry a state route number, and where two routes share the same road GDOT records it under one of them.
- Interstates: I-75
- U.S. highways: US 41, US 341
- State routes (Georgia DOT inventory numbers): SR 7, SR 18, SR 36, SR 109
Parks, Public Land and Water
Lakes and rivers labeled on the map: Potato Creek, Edie Creek, Little Potato Creek, Buck Creek, Big Towaliga Creek and Little Buck Creek. Names follow the U.S. Geological Survey’s official Geographic Names Information System.
For county and city parks, playgrounds and recreation centers, see our Lamar County parks guide.
Neighboring Counties
Lamar County borders Butts County, Monroe County, Pike County, Spalding County and Upson County.
Common Questions
What is the county seat of Lamar County, Georgia?
Barnesville is the county seat of Lamar County. It is also the largest city in the county.
What cities are in Lamar County, Georgia?
Lamar County has 3 incorporated cities and towns: Barnesville, Milner and Aldora.
What counties border Lamar County?
Lamar County borders Butts County, Monroe County, Pike County, Spalding County and Upson County.
Is there a printable map of Lamar County?
Yes. The Lamar County map on this page is a free PDF sized for letter paper (8.5 by 11 inches, portrait) that you can print or save to your phone.
How many people live in Lamar County?
The U.S. Census Bureau estimates 20,690 people lived in Lamar County on July 1, 2024, up from 18,502 in 2020.
Sources we checked
This map and page were built in October 2026 from public data:
- U.S. Census Bureau: TIGER/Line 2023 (county lines, roads, water, place boundaries)
- U.S. Census Bureau: county and city population estimates, Vintage 2024
- U.S. Census Bureau: 2023 Gazetteer (land area)
- USGS: Protected Areas Database of the United States (PAD-US) 4.1 (national forests, refuges, WMAs)
- USGS: Geographic Names Information System (lake and river names)
- Georgia DNR 2026-27 Hunting Regulations (eRegulations) (current WMA list)