Kate Beckinsale was 17 in One Against the Wind when she played the character 'Barbe Lindell'.
That was over 32 years ago in 1991.
This was her first recorded movie acting credit (although may not technically be her first actual acting role).
Today she is 50, and has starred in 49 movies in total, 46 of those since One Against the Wind was released.
In One Against the Wind, I think Kate Beckinsale looks: