In the 18th century, the Spanish church established five Catholic missions along the San Antonio River, primarily to extend its dominion northward from Mexico, but also to convert the native population. What remains of the largest concentration of missions in North America provides an interesting look into Texas' history.

The first mission established in San Antonio, the Alamo (San Antonio de Valero) served as a way station between east Texas and Mexico. It was already 100 years old when it fell in the notorious Battle of the Alamo and became an inspiration and a motivation for liberty during the Texas Revolution.

For 13 days in 1836, around 200 Texas defenders held the Alamo from over one thousand of General Santa Anna's troops. The defenders, William Travis, Jim Bowie, and Davy Crockett, would die fighting overwhelming odds for freedom.

Fifty years ago, the Alamo made its way onto the big screen and into the international consciousness as never before. What John Wayne's historic rendering of Davy Crockett may have lacked in some historical accuracy was more than made up for in impact, to such a degree that nowadays it's hard to tell fact from fiction.

The curvaceous façade and the legend behind it have made their mark on the international consciousness in ways that range from the iconic to the comic; as a symbol of heroism, courage and sacrifice, and, as is the case with any symbol, a target for satire.

Alamo Historian and Curator Bruce Winders says "It's a blessing because people remember the Alamo. We like them to remember it for the history, but sometimes they remember it for something that's irreverent and out of context."

• William Travis' apocryphal "Line in the sand," quoted by thousands, including both presidents Bush.
• Movie and TV appearances ranging from the Lonesome Dove miniseries to King of the Hill to PeeWee's Big Adventure. Not to mention the two big Alamo movies with all-star casts. And who could forget Miss Congeniality with Sandra Bullock's talent contest in front of the Alamo?
• A wealth of songs from artists like Marty Robbins (Ballad of the Alamo), George Strait (Remember the Alamo) and Pete Rowan (Midnight Moonlight).
• Davy Crockett's coonskin caps – about $10,000 a year in sales from the Alamo gift shop.
• Alamo tributes around the globe, from a garden in England to a hand-carved bowie knife in Australia.
• "There was no back door in the Alamo" – a quote attributed to San Antonio Congressman Maury Maverick during President John F. Kennedy's visit.
• A chunk of the Alamo is included in the rock collection that forms part of Chicago's Tribune Tower, along with a piece of the Great Wall of China, the Coliseum and the World Trade Center.
• Alamo Village, which entertained tourists from all over with the movie set from the John Wayne movie; recently closed as a new owner is sought to take over the management of the Bracketville attraction.
• UK's music icon Phil Collins' passion for the Alamo, and largest collection of memorabilia.

Nearly 200 years after the famous siege, the Alamo needs modern-day defenders.

The Daughters of the Republic of Texas, a non-profit organization who are the Alamo's all-volunteer caretakers, have launched the legendary shrine's first-ever membership campaign.

Join Allies of the Alamo and help preserve this icon of American frontier bravery for future generations. As a member, you'll enjoy after-hours tours, discounts, newsletters and behind-the-scenes activities.

Membership levels begin at $30 for students. Become part of the Alamo's history.