Groton House Farm in Hamilton, Massachusetts, owned by the Winthrop family, has undoubtedly made its mark on the sport of eventing in America having hosted horse trials for many decades. With the first dating back to the late 1950s, even before the existence of the United States Combined Training...

Groton House Farm in Hamilton, Massachusetts (Area I) hosts their annual event in late June each year and offers Novice through Intermediate/Preliminary levels. They also offer several unrecognized events throughout the year.