Geography of Duval County
Duval County is classic frontier Texas: 1,793 square miles of open land with only about 9,402 residents, which makes it one of the most thinly settled counties in the state (194th of 254 by density).
It lies in the South Texas region at about 27.68° N, 98.51° W and is one of the 25 largest counties in Texas (13th of 254). Duval County shares boundaries with 6 other Texas counties, and the closest major cities are Laredo (about 62 miles away in a straight line) and Corpus Christi (about 68 miles).
South Texas covers the brush country, the Rio Grande Valley and the ranchlands south of San Antonio. Its culture is strongly shaped by its Tejano heritage and its ties to Mexico, and its economy blends citrus and vegetable farming, ranching, trade and energy.
For a broader view of how Duval County fits within the state, download our free Texas map with counties and cities PDF — a printable, high-resolution reference showing all 254 Texas counties labeled with their county seats.
Population & demographics
With approximately 9,402 residents across 1,793 square miles, Duval County has a population density of about 5.2 people per square mile. Like much of West and South Texas, the county is sparsely populated, with wide-open country between settlements.
County seat: San Diego
If you need an official record from Duval County — a deed, a birth certificate, a court filing — San Diego is where it is kept. Like every Texas county seat, it hosts the courthouse and the main offices of county government. In a county this sparsely settled, San Diego may be one of only a few incorporated towns.
History & name origin
Duval County was established in 1858 and was named for Burr Harrison DuVal (1809–1836), a soldier in the Texas Revolution who died in the Goliad Massacre. It was carved from territory previously part of Live Oak County, Nueces County and Starr County.
Duval County, Texas — frequently asked questions
Quick answers about Duval County geography, population, county seat, neighboring counties, and how to use the maps on this page. Figures are sourced from the U.S. Census Bureau; answers are written and reviewed by the Texas County Map team.
Where is Duval County, Texas located?+
Duval County is located in the South Texas region of Texas at approximately 27.681° N, 98.509° W. It is one of the 254 counties of Texas and carries U.S. Census FIPS code 48131. The interactive map on this page renders the official U.S. Census TIGER boundary for Duval County over real-world OpenStreetMap, Esri satellite, and topographic basemaps.
How big is Duval County in square miles?+
Duval County covers approximately 1,793 square miles of land in the South Texas region — a large county by Texas standards. By land area it ranks 13th out of 254 Texas counties. The full bounding box of the county is rendered to scale on the interactive map and matches the U.S. Census TIGER 2023 polygon.
What is the population of Duval County, Texas?+
Duval County has a population of approximately 9,402 residents. With 1,793 square miles of land, that works out to a population density of about 5.2 people per square mile, which is sparsely populated for a Texas county. That makes Duval County the 169th most populous of the 254 counties in Texas.
What is the county seat of Duval County?+
San Diego is the county seat of Duval County, Texas, which was organized in 1858 and named for Burr Harrison DuVal (1809–1836), a soldier in the Texas Revolution who died in the Goliad Massacre. Duval County was originally carved out of Live Oak County, Nueces County and Starr County. County government offices, courthouses, and most public records for Duval County are located in San Diego.
Which Texas counties border Duval County?+
Duval County shares borders with McMullen, Jim Hogg, Jim Wells, Live Oak, Webb, and Brooks counties. These 6 neighboring counties are highlighted on the schematic boundary map and linked at the bottom of this page so you can quickly compare population, area, and county seats across the South Texas region.
Where can I download or print a map of Duval County?+
Use the "Download PDF" button below the Duval County map on this page to save a letter-size PDF of the county boundary, neighboring counties and incorporated places, drawn from U.S. Census Bureau 2023 boundary files. The "Official TxDOT road map" button downloads the Texas Department of Transportation county road mapbook for Duval County. Both files are stored on this site and download directly. Our free Texas map with counties and cities PDF shows all 254 counties on one sheet.
What is the FIPS code for Duval County, Texas?+
The full 5-digit U.S. Census FIPS code for Duval County is 48131, made up of Texas state code 48 and the 3-digit county code 131. This is the same FIPS code used by the U.S. Census Bureau TIGER/Line files, the American Community Survey, and most federal datasets that key on county.