what did we see?

while in process of cleaning up backyard, after we had a cookout, i was stunned to what i seen in sky. time was about 11pm. coming from the west, at a slow rate of speed (30mph), was a large dark saucer shaped craft. appeared to be 500 feet off ground. 300 ft. dia. it had colored rotating lights around outer edge. underneath was another round appearing dome and it seemed to have large, dimly lit windows. in these windows i still remember seeing figures. not sure what they were. could have been human or what? here is the big mystery. there was no noise at all. i ran inside to get my wife. she seen it too. it went over treetops and we lost sight. this was in 1967 and i thought i would like to share this experience with others. at the time we called local police and newspaper. they showed no interest.
Date is approximate.  PD