Can't answer for GMU79, but I started teaching full-time at Mason in the fall of '71. Went to a few games those first few years in the PE building (now RAC). Building was new that year, I think. (I've talked to some faculty who preceded me at Mason and they indicated that they saw some Mason games at Woodson HS.) Fold-down bleachers--probably started selling season tickets in the Yates years (put tape on bleachers to mark off each "seat".)
Patriot Center opened in 1985.
In George Mason's first season (1966-67), the team played twice against the Lorton Reformatory inmates -
https://gomason.com/news/2017/2/10/mason-marauders-looking-back-at-the-first-mens-basketball-team
"The most memorable games from that first season, though, came against teams from Lorton Reformatory. On Dec. 16, 1966, for their fourth game of the season, the Marauders headed 12 miles south down Route 123 to what is now Laurel Hills, Va., to play inmates from Lorton Reformatory.
Yes, inmates. Operated by the District of Columbia Department of Corrections, Lorton Reformatory was a prison built in 1910.
'We must have been the first college team to ever go play a game at Lorton,' Campen said. 'That was mind-blowing. I remember thinking, "What the hell do we have ourselves into here?'" I had never encountered anything like that in my high school career. You could imagine the things that were said (by the inmates). They were just having a good, ole time at our expense.'
Campen recalls the game being played in a cage separating the court from more than 500 inmates in attendance . The scorebook from that game reads names such as Big Deal, Slim Carrol, Pop Crump, Joe Ball, Mouse Wheeler and Rat Parker. But while those watching made the environment intense, Lorton's players were surprisingly friendly."
"As unforgettable of a game as it was at the prison, the scene was just as interesting when Lorton came to Fairfax to play the Marauders at Woodson High School that February. More than 300 fans packed the stands for the game – many of them cheering for the visiting team.
'I think we had more state troopers than we had fans from George Mason,' Campen says, laughing. 'There were probably a couple hundred family members from Washington, D.C. who came out to see their boyfriends, fathers and uncles play basketball because they had a chance to see them. I think that was the biggest crowd we ever had at a home game and that was all rooting for Lorton."
Mason lost twice to Lorton and finished with a 6-12 record overall that year. Even so, the dozen or so young men on the 1966-67 team at George Mason look back fondly on that first season of men's basketball at George Mason."