Geography of Castro County
Castro County is a rural county of 898 square miles and about 7,295 residents, where farms and ranches fill most of the space between Dimmitt and its smaller communities.
It lies in the West Texas region at about 34.53° N, 102.26° W and is 159th in size among Texas's 254 counties. Castro County shares boundaries with 6 other Texas counties, and the closest major cities are Amarillo (about 54 miles away in a straight line) and Lubbock (about 70 miles).
West Texas is a land of long horizons: rolling plains, mesas and desert grassland where cotton farms, cattle ranches and the oilfields of the Permian Basin are the main sources of work. Distances between towns are measured in hours, not minutes.
For a broader view of how Castro 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 7,295 residents across 898 square miles, Castro County has a population density of about 8.1 people per square mile. Like much of West and South Texas, the county is sparsely populated, with wide-open country between settlements.
County seat: Dimmitt
County government for Castro County is based in Dimmitt. The commissioners court, made up of a county judge and four precinct commissioners, meets here and sets the county budget, roads policy and tax rate. For many residents, a trip to Dimmitt combines county business with groceries, school events and church.
History & name origin
Castro County was established in 1876 and was named for Henri Castro (1786–1865), a French consul general for the Republic of Texas and founder of a colony in Texas. It was carved from territory previously part of Bexar County.
Castro County, Texas — frequently asked questions
Quick answers about Castro 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 Castro County, Texas located?+
Castro County is located in the West Texas region of Texas at approximately 34.530° N, 102.262° W. It is one of the 254 counties of Texas and carries U.S. Census FIPS code 48069. The interactive map on this page renders the official U.S. Census TIGER boundary for Castro County over real-world OpenStreetMap, Esri satellite, and topographic basemaps.
How big is Castro County in square miles?+
Castro County covers approximately 898 square miles of land in the West Texas region — a mid-sized Texas county. By land area it ranks 159th 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 Castro County, Texas?+
Castro County has a population of approximately 7,295 residents. With 898 square miles of land, that works out to a population density of about 8.1 people per square mile, which is sparsely populated for a Texas county. That makes Castro County the 183rd most populous of the 254 counties in Texas.
What is the county seat of Castro County?+
Dimmitt is the county seat of Castro County, Texas, which was organized in 1876 and named for Henri Castro (1786–1865), a French consul general for the Republic of Texas and founder of a colony in Texas. Castro County was originally carved out of Bexar County. County government offices, courthouses, and most public records for Castro County are located in Dimmitt.
Which Texas counties border Castro County?+
Castro County shares borders with Hale, Lamb, Swisher, Parmer, Randall, and Deaf Smith 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 West Texas region.
Where can I download or print a map of Castro County?+
Use the "Download PDF" button below the Castro 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 Castro 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 Castro County, Texas?+
The full 5-digit U.S. Census FIPS code for Castro County is 48069, made up of Texas state code 48 and the 3-digit county code 069. 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.