Short answers, pulled from the story.
San Antonio was founded on the 5th of May 1718 when the Presidio San Antonio de Béxar was commissioned. The Spanish expedition led by Domingo de Terán and Alonso de León first discovered the river on the 13th of June 1691.
The Battle of the Alamo raged from February 23 to the 6th of March 1736 ending with the death of every defender including James C. Neill, William Barrett Travis, and James Bowie. This defeat became a rallying cry for the Texian Army that later defeated Santa Anna at San Jacinto.
The U.S. Census Bureau reported San Antonio had 1,434,625 residents in 2020 making it the seventh-most populous city in the United States. The metropolitan area housed approximately 2.76 million residents ranking third-largest in Texas after Houston and Dallas-Fort Worth.
San Antonio hosts Lackland Air Force Base where over 35,000 new recruits undergo basic training each year through the 737th Training Group. Fort Sam Houston houses METC the largest medical education center globally with 24,000 annual graduates across 30 programs.
Five Spanish frontier missions including The Alamo were designated UNESCO World Heritage sites on the 5th of July 2015 becoming Texas's first such site. These missions include Mission Espada which is part of the River Walk extending between Brackenridge Park and Loop 410 South.