The purpose of this chapter is to map and analyse the use of horses in sport using Allen Guttmann’s definition of modern sport. This chapter will focus especially on women’s entrance into different events, in congruence with Guttmann’s characteristic of “equality”, which demands that nobody is excluded from participation in sports due to factors such as age, social class, ethnicity, gender and (dis)ability. It will be argued that equestrianism can only be defined as modern sport, in Guttmann’s sense of the concept, if men and women, able-bodied/disabled persons, members of all social classes, and non-majority ethnicities can partake in competitions. In this chapter, the analysis will be limited to horse racing, equestrian competitive activities organized by Fédération Equestre Internationale (FEI) and Olympic events. These sport activities emerged as masculine activities, practised by men. This chapter will analyse the point at which they were opened to women, and the circumstances leading to gender inclusivity, also tentatively discussing gender constructions in the different sports.