Irion County Texas map
31.30° N · 100.98° W · County seat: Mertzon · 1,052 sq mi
Irion County has 1,513 residents, one incorporated town and 1,052 square miles of Edwards Plateau ranch land — about a person and a half per square mile. It also has a courthouse in a town that lost the county seat and a piece of the Spraberry Trend, one of the largest oil fields in the country, under its northern range.
Mertzon lies on US-67 in the northeast of the county, on the rail line southwest of San Angelo. Sherwood, the old seat, is a few miles north of it.
Where Irion County is
The county lies southwest of San Angelo on the plateau, where the Middle Concho drainage runs out into dry draws. San Angelo is 34 miles northeast and is the only city anywhere near; Big Spring is 72 miles northwest, Midland 80 miles northwest and Odessa 90 miles northwest.
Only four counties touch it, an unusually small number: Tom Green wraps around the north and east, Schleicher is southeast, Crockett southwest and Reagan west.
Irion County was cut out of Tom Green County in 1889 and named for Robert Anderson Irion, a physician who served as secretary of state under Sam Houston in the Republic of Texas. It is one of a ring of counties — with Coke, Sterling and Reagan — carved from the enormous original Tom Green County in the space of a few years.
Sherwood, Mertzon and a moved courthouse
The first county seat was Sherwood, laid out beside Spring Creek when the county organized. It built a native stone courthouse at the turn of the century and expected the railroad. The railroad, when it came, ran a few miles south instead, and the town of Mertzon grew up at the track as the shipping point for wool, mohair and cattle. In 1936 the voters moved the seat to Mertzon. The old courthouse at Sherwood still stands, empty of county business, in what is now a near-ghost town — one of the few surviving abandoned courthouses in Texas.
Barnhart, in the southwest of the county on the same rail line, was for a period one of the busiest wool and mohair shipping points in the state. Both it and Sherwood are unincorporated today.
Towns
| Place | Type | Population (2020) |
|---|---|---|
| Mertzon (county seat) | City | 752 |
Mertzon is the county's only incorporated place and holds about half its population.
Roads
- US-67 – the main route, running northeast to San Angelo and southwest through Barnhart toward Big Lake and the Permian Basin.
- SH-163 – south from Mertzon through Barnhart and on to Ozona in Crockett County; north it continues toward Sterling City.
Two numbered routes for a thousand square miles. There is no interstate; the nearest is I-10, reached by SH-163 south to Ozona, or I-20 by way of San Angelo and US-87.
Ranches and oil
Land in Irion County is held in a small number of very large ranches, most of them running sheep, Angora goats and cattle on shallow range that will support little else. That pattern — few owners, large blocks, long tenure — is the reason the county's population has stayed near 1,500 through boom and bust alike, and why there is no second town.
Beneath the northern part of the county lies the southern edge of the Spraberry Trend, which by remaining reserves is among the largest oil fields in the United States. Horizontal drilling in the Spraberry and Wolfcamp intervals brought new activity to the northwest of the county in the 2010s, and oil and gas valuation supplies a large share of the county tax roll. Mineral income, not population, is what keeps a county this empty solvent.