Katsuhiro Yamahata

On February 23, 1975, Katsuhiro Yamahata and his classmate Masato Kono (also referred to as Kawano in some accounts) were roller-skating near the Hinode Housing Estate in Kōfu City, Yamanashi, when they witnessed two orange, glittering UFOs. One craft descended into a nearby vineyard, where the boys encountered a fanged humanoid that tapped Yamahata on the shoulder and made sounds like a backwards tape recorder, causing him to collapse in fear.

The incident is considered one of Japan’s most credible UFO cases, supported by physical evidence including structural damage to concrete pillars in the vineyard and consistent testimony from multiple witnesses, including the boys' mothers and a classmate who saw the craft earlier. Yamahata, who later became known for his continued interest in UFOs, participated in the 50th-anniversary commemoration in 2025, which helped cement Kōfu’s reputation as a "UFO City."