The Rendelsham Forest incident of 1980 is still, IMO, the most compelling evidence we have of UFOs.
Nowadays, people can easily wave away UFO sightings as secret modern technology or drones, but that's a lot harder to do for an event that happened in 1980. It's even more compelling that it was seen by multiple military personnel. They didn't only see the things with their eyes, but there were also visible markings on the ground and unusual radiation traces I'm the area.
This is a pretty decent video (ignore the cartoon art style). The only one I could find that included the supposedly the original recording from the US troops who encountered the object. I have no idea if the recordings are real, but if they're fake then they're a decent fake.