The marker makes the Dome a Recorded Texas Historic Landmark, meaning it is both "historically and architecturally significant."
The Eighth Wonder of the World is already a State Antiquities Landmark and has the title of being on the National Register of Historic Places.
Speakers at the Tuesday afternoon ceremony included Harris County Judge Ed Emmett and Dene Hofheinz, daughter of Roy Hofheinz, who is most associated with the creation of the Astrodome.
The Texas State Historical Marker was sponsored by the Houston Astros.
The Astrodome hosted the Astros from 1965 to 1999 and the Oilers from 1968 to 1996.
The Dome was condemned and closed to the public in 2009.
No description foundIn an April 1965 file photo, the baseball field and seats at the Houston Astrodome are seen through a fish-eye lens in Houston. (AP Photo/File)Workmen zipper up the Astroturf carpet completely covered the outfield, workers spread the warning track gravel along the fence in Houston on July 13, 1966. (AP Photo/Ed Kolenovsky)Muhammad Ali fights with Ernie Terrell on Feb. 6, 1967 at the Houston Astrodome in Houston, Texas. (AP Photo/HT)Guy V. Lewis, University of Houston basketball coach, lets out a war whoop as he is carried to the dressing room by happy fans after the Houston Cougars' upset over the UCLA Bruins in the Houston Astrodome, Jan. 20, 1968. (AP Photo/Ed Kolenovsky)This is an aerial view of the Houston Astrodome, from May 1, 1967. (AP Photo)Bobby Riggs goes after a quick shot by Billie Jean King in the winner-take-all match in the Astrodome in Houston, Tex., on Sept. 20, 1973. (AP Photo)Seattle Seahawks middle linebacker Terry Beeson tries to stop Houston Oilers Earl Campbell by grabbing his feet, but Earl broke the tackle for a nine-yard gain in the fourth quarter at the Astrodome in Houston, Oct. 12, 1981. Campbell carried 39 times for 189 yards as the Oilers beat the Seahawks 35-17. (AP Photo/F. Carter Smith)Houston Astros pitcher Mike Scott is carried by teammates Jim Deshaies, left, and Kevin Bess after his no-hitter game against the San Francisco Giants in the Houston Astrodome in Houston, Texas, Sept. 25, 1986. The Astros won 2-0 to clinch the National League Western division. (AP Photo)Nearly half the seats were empty in Houston's Astrodome as the Houston Oilers play the Cincinnati Bengals on Sunday, Nov. 12, 1995. Oilers owner Bud Adams has cited lack of fan interest as one of his reasons for moving the team to Nashville, Tenn.. (AP Photo/Michael Stravato)Video images of former President Ronald Reagan are projected at two big screens as Reagan speaks to the assembly of the Republican National Convention at the Astrodome in Houston, Texas, on August 17, 1992. (AP Photo/Jim Mone)Fireworks explodes in the Astrodome as the Chicago Cubs, left, and Houston Astros lined up before the start of the last season opener to be played in the Astrodome, Tuesday, April 6, 1999, in Houston. The Astros will begin the 2000 season in a new balpark in downtown Houston. (AP Photo/Pat Sullivan)The floor of Houston's Astrodome is covered with cots and evacuees from hurricane ravaged New Orleans Friday, Sept. 2, 2005. (AP Photo/Pat Sullivan)In this May 21, 2012, file photo, rows of dirty, tattered seats ring the Astrodome in Houston. Once touted as the Eighth Wonder of the World, the nation's first domed stadium sits quietly gathering dust and items for storage. The National Trust for Historic Preservation put the Astrodome on its 2013 list of 11 Most Endangered Historic Places. (AP Photo/Pat Sullivan, File)
What's next for the Dome
Harris County commissioners in February approved a multimillion-dollar plan that would repurpose and renovate the Astrodome.
The $105 million plan would include raising the Astrodome's floor to create an underground parking garage and 9 acres of open space.
The space is expected to be used for conferences, festivals and, potentially, commercial space.
The money to pay for the renovations would come from the county's general fund of property taxes, hotel occupancy taxes and parking fees.
Construction is expected to start in October 2018 and would take 17 months to complete.
