Once upon a time, a long time ago, there were Thoroughbreds that could carry heavy weight assignments, set multiple track records, run 16 to 20 times a year … then come back the next year, and the next year, and do it all again.

In the modern world of horse racing – an era in which the connections of champion racehorses carefully pick their spots and rarely race more often than once a month – it can be incredible to reflect on the careers of true “iron horses” like Discovery.