Texas Military Forces sparked the Texas Revolution at the Battle of Velasco and became legendary at the Battle of Gonzales (the "Lexington of Texas"). Their legend continued at their defeat by Mexican forces at Siege of the Alamo, with events such as the Immortal 32 and To the People of Texas &amp; All Americans in the World, which resulted in one of the most notable last stands in history. As of 2018, the Alamo Mission is the most visited tourist attraction in Texas and one of ten manmade UNESCO World Heritage Sites in the United States. The Texas Military's legend was sealed at the Battle of San Jacinto, when they defeated Santa Anna's army in 18 minutes, achieving independence from the Centralist Republic of Mexico and establishing the Republic of Texas, one of three colonies to win independence without foreign aid in world history and the only American state (the Thirteen Colonies were aided by France, and the California Republic and Republic of Hawaii were aided by the United States). The artillery used during the battle, the Twin Sisters, are considered the "Holy Grail of Texas".