Henry Callahan (1957–1982) was a player and ambassador of Ultimate and helped bring the sport to the University of Oregon, formally establishing a team in 1978.
A Callahan is when a defensive player intercepts the disc in the opponent's end zone for a point.
It is a rare occurrence, because it requires a defender to intercept, rather than simply block, a pass in the offense's own end zone.
The move is so called because it was first legalized as a goal (rather than needing to be put into play from the goal line) in the Callahan version of the rules, which differed from the Ultimate Player Association's current rules at the time.
[citation needed] Completed in 1992 and expanded in 2008, this course is located in Henry Callahan Memorial Park.