43 miles SE of Las Cruces, New Mexico; 564 miles NW of San Antonio; 617 miles W of Dallas

Here, in the sun-swept, mountainous desert of Texas's westernmost corner, is El Paso, the state's fifth-largest city. Built between two mountain ranges on the shores of the Rio Grande, the city is an urban history book, with chapters dedicated to Spanish conquistadors, ancient highways, gunfighters, border disputes, and modern sprawl.

El Paso's rich history is a result of its geography. The Franklin Mountains, which now border the downtown area and occupy the city's heart, offered natural defense for the American Indians who inhabited the area for more than 10 millenniums; the Rio Grande offered water. As the mountains slope into a vast canyon, the Spanish explorers who first crossed the Rio Grande in the 16th century saw it as an ideal north-south route, one that soon became known as the "Camino Real" (or "King's Highway") and served as a principal trade route for nearly 300 years.

With the 17th century came an influx of Catholic missionaries, a group that established numerous missions that survive today. But Spain saw its grip weaken, and a Mexican flag flew over El Paso when independence was established in 1821. This era was short-lived, as Mexico ceded the land north of the Rio Grande to the United States following the Mexican-American War (1846-48). After the railroad arrived in 1881, El Paso became a commercial center and also earned the nickname "Sin City," thanks to the saloons, brothels, and casinos that lined every major street. Many notorious gunfighters -- including Billy the Kid and John Wesley Hardin -- called the city home.

El Paso boomed in the early 20th century and again following World War II, entrenching itself as a center for agriculture, manufacturing, and international trade. The city's relationship with Ciudad Juárez has been symbiotic for centuries, even more so since the resolution of a century-old border dispute in the 1960s and the signing of the North American Free Trade Agreement in 1994. Unfortunately, increased border security and a wave of drug-related violence in Juárez have put a damper on the sister cities' relationship in recent years.

Nevertheless, in comparison with the relative wealth and glitz of Santa Fe or Tucson, El Paso is in many ways the authentic Southwest -- unpolished, undiluted, and honest. Separated by a swath of the Rio Grande, El Paso and Ciudad Juárez each represent their country's largest border city, and the local culture, a fusion of Mexican and American traditions, is distinct and unique in comparison to the way of life in eastern Texas. A day or two of exploration is worthwhile; take the time to wander downtown, enjoy a meal at one of the city's terrific Mexican restaurants, and gain a better understanding of what a border town is all about.