UFO reported by radar in Greece in 1958

Summary

In November 1958, a Greek pilot observed unusual contrails at high altitude near Volos. These contrails moved rapidly eastward and then disappeared northward. The pilot estimated their speed at 500 knots, an exceptionally high figure. Although he reported to radar stations, no contact with the unknown object was achieved. The lack of concrete data made it difficult to evaluate the phenomenon. This case remains an unsolved mystery.