The Alamo, likely the only landmark in history to play both a pivotal role in the struggle for Texan independence and get screen time with Pee-wee Herman, was just named a UNESCO World Heritage Site on Sunday. The first such building to be honored in Texas, it marks the culmination of a nine-year campaign to designate the city's five historic missions (Concepción, San Jose, San Juan and Espada have also been given UNESCO status). The site of a final stand by patriots and American icons such as Jim Bowie and David "Davy" Crockett, as well as a massive driver of tourism and tax revenue (a recent study suggested the designation could generate more than $100 million in additional economic activity), the case for nomination and preservation seems rock solid. But back in the '20s, when some of these Missions were crumbling and urban growth looked like a threat, a few forward-thinking women stepped in to save these symbols of San Antonio.

The Roaring '20s weren't so kind to San Jose, the "Queen of the Missions," according to a recent San Antonio Magazine article, despite the boom happening in what was then the largest city in Texas. Doors were missing and the façade was crumbling at the landmark structure. A caretaker was even caught stripping and selling brass decorations a few years before the bell tower collapsed. While the Daughters of the Republic of Texas had already become involved in preserving the Alamo, the sister sites needed help.

The saviors of these buildings came in the form of two artists, Rena Maverick Green and Emily Edwards, both travelers with a common interest in preserving the city's history and heritage. They formed the San Antonio Conservation Society in March of 1924 to help save these important buildings. Green, granddaughter of a signer of the Texas Declaration of independence, was both a sculptor and painter, and also worked with the National Women's Party of Texas to secure a women's right to vote. Edwards, an artist in her own right who later became friends with Diego Rivera, was the group's first president. She used some intriguing concepts to convince politicians of her cause; to make the case for preserving a section of the San Antonio River, she put on a puppet show for city commissioners called "The Goose and the Golden Eggs".

One of perhaps the first organizations to seek preservation of the built environment—the National Trust for Historic Preservation wasn't formed until the late '40s—the SACS was trailblazing, its 13 original all-female members dedicated to ""co-operate in the preservation of the Missions, to conserve Old Buildings, Documents, Pictures, Names, Natural Beauty, and anything admirably distinctive of San Antonio." Their methods and early successes also set them apart. Ignacio Salcedo, a bootlegger who owned part of the Mission San Jose, refused to sell his land for less than $10,000, but when he was arrested for gambling and selling booze, he cut his price in half (if the women covered his bail). Eventually, the organization secured the necessary land and oversaw the Missions, and in 1983, handed them over to the National Park Service. Their fundraising and vision proved vital to saving what are now internationally recognized heritage sites.

∙ On a Mission [San Antonio Magazine]

∙ Mapping The Imperiled 20th-Century Buildings Who've Recently Found a Hero in the Getty Foundation [Curbed]

∙ National Historic Trust's List of 11 Most Endangered Places Focuses on American Diversity [Curbed]