The 1966 U.S. Open was the 66th U.S. Open, held June 16–20 at the Lake Course of the Olympic Club in San Francisco, California. Billy Casper, the 1959 champion, staged one of the greatest comebacks in history by erasing a seven-stroke deficit on the final nine holes to tie Arnold Palmer; he then prevailed in an 18-hole playoff to win the second of his three major titles. It was the fourth playoff in five years at the U.S. Open, and the third for Palmer, the 1960 champion. U.S. Open 1966: June 16–20, 1966 at Olympic Club, Lake Course. Champion: Billy Casper, at 278 (−2), playoff — 2nd major title. Wiki link