Based on the architecture and the surrounding landscape, this is a view of the grandstands at Indianapolis Motor Speedway, likely taken during the mid-to-late 1960s.
Specifically, these appear to be the North Vista grandstands (located outside Turns 3 and 4). You can tell by the distinct concrete support structures and the way the trees are integrated into the viewing area, which was a hallmark of that section of the track during that era.
The Cars: The parking lot is a goldmine for dating this photo. You can see a red 1961 Dodge Dart station wagon (the one with the distinct diagonal fins) and a white 1964 or 1965 Plymouth Valiant next to it.
The Crowd: The packed stands suggest this was taken during a major event—most likely the Indianapolis 500 or one of the high-profile qualifying days (Time Trials).
The Fashion: The attire of the people walking in the foreground—short-sleeved button-downs and simple summer dresses—perfectly matches the mid-60s aesthetic.
It’s a great shot because it captures the "fan experience" of the era, showing how close the parking and picnic areas were to the actual track structure.