<P> In 1931, Driscoll persuaded the state legislature to purchase two tracts of land between the chapel and Crockett street . In 1935, she convinced the city of San Antonio not to place a fire station in a building near the Alamo; the DRT later purchased that building and made it the DRT library . During the Great Depression, money from the Works Progress Administration and the National Youth Administration was used to construct a wall around the Alamo and a museum, and to raze several non-historic buildings on the Alamo property . </P> <P> The Alamo was designated a National Historic Landmark on December 19, 1960, and was documented by the Historic American Buildings Survey in 1961 . It was an inaugural listing on the National Register of Historic Places in 1966, and is a contributing property to the Alamo Plaza Historic District, which was designated in 1977 . As San Antonio prepared to host the Hemisfair in 1968, the long barracks was roofed and turned into a museum . Few structural changes have taken place since then . </P> <P> According to Herbert Malloy Mason's Spanish Missions of Texas, the Alamo is one of "the finest examples of Spanish ecclesiastical building on the North American continent". The mission, along with others located in San Antonio, is at risk from environmental factors, however . The limestone used to construct the buildings was taken from the banks of the San Antonio River . It expands when confronted with moisture and then contracts when temperatures drop, shedding small pieces of limestone with each cycle . Measures have been taken to partially combat the problem . </P> <P> In 1988, a theater near the Alamo unveiled a new movie, Alamo...the Price of Freedom . The 40 - minute - long film would be screened several times each day . The movie attracted much protest from Mexican American activists, who decried the anti-Mexican comments and complained that it ignored Tejano contributions to the battle . The movie was re-edited in response to the complaints, but the controversy grew to the point that many activists began pressuring the legislature to move control of the Alamo to the League of United Latin American Citizens (LULAC). In response to pressure from Hispanic groups, state representative Orlando Garcia of San Antonio began legislative hearings into DRT finances . The DRT agreed to make their financial records more open, and the hearings were canceled . </P>

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