Perhaps the most widely witnessed and documented UFO sighting in history, The Phoenix Lights are one of the most famous mass UFO sightings of all time. To this day, fanatics and investigators continue to study footage of the lights. On the evening of March 13th, 1997, thousands of Phoenix residents looked up at the night sky hoping to catch a glimpse of the Hale-Bopp comet, but instead saw red-orange balls of light hovering over their city. That same evening, reports flooded in across the entire state of Arizona of a v-shaped craft slowly moving through the state. People claimed the craft was nearly a mile wide, larger than any aircraft ever known to man. The US government still claims the lights were nothing more than a flare test, but to this day the lights remain unexplained.