When 30,000 runners lace up and await the starting gun at this year’s Boston Marathon on April 18, close to half will be women.

But just 45 years ago, women could not run this race, one of the oldest and toughest in the world. Much has changed for women runners at Boston and around the globe.

Infographic describing increase in participation by women in Boston Marathon (State Dept./Julia Maruszewski)
(State Dept./Julia Maruszewski)

ShareAmerica writer Pamela M. Prah contributed to this article.