I saw it too! RE: Football sized saucer over Hagerstown, MD in summer of 1974

While I was cleaning up the remains of an outside dinner I saw this craft that was HUGE, to a little kid, just hovering silently. My view of the craft was slightly obstructed by the house but I clearly remember it had different colored lights (red, blue, yellow) slowly revolving around its perimeter. I don't remember how long it stayed but I remember just staring at it for what seemed a long time and then it just sped away.
 I've always wondered what it was and for the longest time just assumed it was something that was associated with the county fair. Then I read the account from another couple seeing the same thing. I lived approximately 6 miles from West Franklin Street, on Day Road.
 Pretty amazing!
Witness indicates that the date of the incident is approximate.  PD