San Antonio is the second-largest city in the state of Texas and the seventh largest city in the United States. Located in South Texas, the city is a cultural and geographical gateway into the American Southwest. San Antonio is the seat of Bexar County with a population of 1,328,984 as of the 2007 U.S. Census estimate. It was the fourth-fastest-growing large city in the nation from 2000-2006. Its metropolitan area has a population of 2,031,445 based on the 2008 U.S. Census estimate, making it the 28th-largest metropolitan area in the U.S and third in Texas (behind Dallas and Houston).

San Antonio was named for the Portuguese St. Anthony, whose feast day is on June 13, when a Spanish expedition stopped in the area in 1691. The city has a strong military presence—it is home to Fort Sam Houston, Lackland Air Force Base, Randolph Air Force Base, and Brooks City-Base, with Camp Bullis and Camp Stanley right outside the city. Furthermore, Kelly Air Force Base (now Port San Antonio) operated out of San Antonio until 2001, when the airfield was transferred over to Lackland AFB and the remaining portions of the base became an industrial/business park. The decision to close Kelly and consolidate its resources came from the 1995 BRAC. San Antonio is also home to the South Texas Medical Center, the only medical research and care provider in the South Texas region.

Famous for its River Walk, the Alamo, Tejano culture, and home to the SeaWorld San Antonio and Six Flags Fiesta Texas theme parks, the city is visited by approximately 26 million tourists per year according to the San Antonio Convention and Visitors Bureau. San Antonio is also home to the first museum of modern art in Texas, known as the McNay Art Museum.

Native Americans originally lived in (near) the San Antonio River Valley, in the San Pedro Springs area, calling the vicinity "Yanaguana," meaning "refreshing waters."

In 1536, Álvar Núñez Cabeza de Vaca, a shipwrecked captive of Native Americans, visited the interior of what would later be called Texas. He saw and described the river later to be named the San Antonio.

In 1691, a group of Spanish explorers and missionaries came upon the river and Native American settlement (located in the area of present-day La Villita) on June 13, the feast day of Saint Anthony of Padova, Italy and named the place and river "San Antonio" in his honor.

In 1716, The Spanish Council of War approved a site on the San Antonio River for construction of a fortified presidio (fort). The Domingo Ramón expedition, accompanied by the trader St. Denis from Louisiana (who had come to the site two years previous) established a presidio on the river. That council also approved a request by Father Olivares to establish a Catholic Mission at the site.

In 1718, Martin de Alarcón, then Governor of Texas, reinforced the presidio and the ten soldiers and their families were recognized officially as the beginning of the villa. Alarcón named the presidio San Antonio de Béjar in honor of the Duke of Béjar, in Spain, the viceroy's brother, who died what was considered a hero's death defending Budapest from the Ottoman Empire in 1686.

That same year, the Mission of San Francisco de Solano was moved from the Rio Grande to merge with Mission San Antonio de Padua. Father Olivares renamed his merged mission Mission San Antonio de Valero. The presidio, the villa and the mission comprised the municipality named San Antonio de los Llanos (of the Plains) by Governor Alarcón. One year later, in 1719, Mission San Antonio moved to its second site on the east bank near the present day St. Joseph's Church on Commerce. (The names are in dispute because there are no such saints and only a Pope can name saints.)

In 1721, The Marquis de Aguayo moved the presidio San Antonio de Béjar to its present site on the Plaza de Armas, where permanent quarters were constructed for the soldiers. In 1726 the official settlement population was 200, including 45 military and their families.

The Mission San Antonio was moved to its third and final site on Alamo Plaza in 1724 because of hurricane flooding at the previous location.

At eleven o'clock on the morning of March 9, 1731, sixteen families (56 people) from the Canary Islands, often referred to as the "Canary Islanders," arrived at the Presidio of San Antonio de Bexar in the Province of Texas. By royal decree of the King of Spain, they founded La Villa de San Fernando and established the first civil government in Texas.The Marquis of Casafuerte, Viceroy of Spain, (King of Spain) bestowed upon each Canary Island family titles of nobility. Many descendants of these first settlers still reside in San Antonio.

The Battle of the Alamo took place in 1836, and eventually the town would grow to encompass the mission where the battle took place, a mile to the east. This was where 189 defenders, both Mexicans and settlers, were besieged in the old mission against 4,000 Mexican troops led by Antonio López de Santa Anna for 13 days. The defenders were all killed in the final assault on the garrison. Some recent evidence suggests there might have been a few prisoners, Colonel Davy Crockett perhaps among them, that were executed after the battle had ended. The cry "Remember the Alamo" became the rallying point of the Texas Revolution. Texas independence was finally attained at the subsequent Battle of San Jacinto the following April.

Like many municipalities in the American Southwest, San Antonio experiences steady population growth. The city's population has nearly doubled in 35 years, from just over 650,000 in the 1970 census to an estimated 1.2 million in 2005 through both steady population growth and land annexation (considerably enlarging the physical area of the city).

The Alamo is a former Roman Catholic mission and fortress compound. It is maintained as a shrine and museum located in the heart of downtown, and is surrounded by many hotels and tourist attractions. It is clearly San Antonio's best known landmark, and is featured in its flag and seal and in the city's nickname, "The Alamo City." Across the street from the Alamo is the world famous Crockett Hotel, named after the legendary pioneer Davy Crockett.

San Antonio is a popular tourist destination. The jewel of the city is the River Walk, which meanders through the downtown area. Lined with numerous shops, bars, and restaurants, as well as the Arneson River Theater, this attraction is transformed into an impressive festival of lights during the Christmas and New Year holiday period, and is suffused with the local sounds of folklorico and flamenco music during the summer, particularly during celebrations such as the Fiesta Noche del Rio. Also based along the River Walk is the newly restored Aztec On The River, the only surviving exotic-themed movie palace in Texas.

The Alamo, located nearby, is Texas' top tourist attraction, while the River Walk is the second most visited attraction. SeaWorld, located 16 miles west of the city, is the number 3 attraction.

The downtown area also features Cathedral of San Fernando, The Majestic Theatre, HemisFair Park (home of the Tower of the Americas and the Institute of Texan Cultures), La Villita, El Mercado, the Spanish Governor's Palace, and the historic Menger Hotel. On the northern side of the Alamo complex, beside the Emily Morgan Hotel, is the San Antonio Cavalry Museum, which features cavalry artifacts and exhibits and is frequented by local re-enactors.

The Fairmont Hotel, built in 1906, is in the Guinness World Records as one of the heaviest buildings ever moved intact. It was placed in its new location, three blocks south of the Alamo, over four days in 1985, and cost $650,000 to move.

Other places of interest include the The Woodlawn Theatre, the San Antonio Zoo, the Japanese Tea Gardens, Kumamoto En, Brackenridge Park, the missions of the San Antonio Missions National Historical Park, the Museo Alameda, the San Antonio Museum of Art, the McNay Art Museum, the Witte Museum, ArtPace, Blue Star Contemporary Art Center, SeaWorld San Antonio, Six Flags Fiesta Texas, the Texas Transportation Museum, and Splashtown San Antonio. Visitors can also experience something of the cowboy culture year round, they can see the 40-foot (12 m) tall cowboy boots at North Star Mall.

Beyond taking in the sights and sounds of San Antonio, tourists can sample some of its world famous Tex-Mex cuisine at the many fine restaurants located throughout the city. Mexican restaurants are abundant in virtually all parts of town, and most — except for those in the Far North and some of the Uptown enclaves like Alamo Heights — are relatively inexpensive. Some outstanding examples of Tex-Mex eateries include Jacala, on West Avenue on the near Northwest side, La Hacienda de Los Barrios, on the North East side, Tommy's on Nogalitos at I-35 near downtown, and Los Barrios, on the near North side of town.