Silent slow flying triangular aircraft.The aircraft was a triangle, 100 to 150 foot wing span. Three white lights on each side of the leading edge for a total of six lights. No other lights. The aircraft was completely silent. It was flying less than 100 mph and at an altitude less than 300 feet. It flew straight north over Marsh Miller lake near Bloomer, Wisconsin. The altitude and speed was constant. No photos or video was taken. I was in awe of what I was seeing. This was not any drone I have ever seen. It was too large.