True story... I saw The Allman Brothers Band, the Grateful Dead, and The Band in the summer of 1973 at the DC baseball stadium (back when The Washington Senators still existed). Later that summer they appeared at the record-setting summer jam at Watkins Glen, where 600,000 witnessed the performance.
We had to leave early (2 AM) because my date didn't tell her mom we were going to a concert in DC. My friend - a Grateful Dead fan - was *not* happy.
Lots of wacky weed everywhere, and a day-leading-into-night full of music.