How a surveying error gave Texas an extra 1,000 square miles

Countries & Cities · Published 12 October 2026 Swipe more like this →

In short: The borders of the Texas Panhandle were shaped by international treaties and mid-19th-century politics. However, a significant portion of its western edge exists because of a simple mathematical mistake made by surveyors in 1859, leaving the state with land that was technically intended for New Mexico.

The Texas Panhandle is a square-shaped region comprising the northernmost 26 counties of Texas. Its boundaries are a complex legacy of 19th-century diplomacy. The eastern border at the 100th meridian west was established by the 1819 Adams–Onís Treaty between the United States and New Spain. Meanwhile, the western boundary was set by the Compromise of 1850, which placed the border at the 103rd meridian west, separating the panhandle from the New Mexico Territory.

The region's western edge, known as the Cimarron Meridian, was first surveyed in 1859. This process was flawed; the survey placed the boundary between 2 and 4 miles too far west. Because surveyors in Oklahoma were more accurate, the Texas Panhandle actually extends further west than the Oklahoma Panhandle. This error resulted in Texas possessing nearly 1,000 square miles of land that the Compromise of 1850 had intended to belong to New Mexico.

The area features the level Llano Estacado alongside the striking Palo Duro Canyon, which ranks as America's second-biggest canyon. Life in this semi-arid High Plains region relies heavily on the Ogallala Aquifer and Lake Meredith for fresh water. While the area is sparsely populated, with a 2010 density of only 16.6 people per square mile, the Amarillo metropolitan area serves as a major urban hub, containing over 72% of the region's residents.

The demographic makeup of the region, according to 2020 census data, is 53.6% non-Hispanic White and 35.2% Hispanic. The population is notably stable in its origins, with approximately 92.3% of inhabitants claiming native birth.

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