The Shire horse is a breed of draught horse (BrE) or draft horse (AmE). The breed comes in many colours, including black, bay and grey.They are a tall breed, with mares standing 16 hands (64 inches, 163 cm) and over and stallions standing 17 hands (68 inches, 173 cm) and over.The breed has an enormous capacity for weight pulling, and Shires have held the world records for both largest overall horse and tallest horse at various times.hey are a tall breed, with mares standing 16 hands (64 inches, 163 cm) and over and stallions standing 17 hands (68 inches, 173 cm) and over. The breed has an enormous capacity for weight pulling, and Shires have held the world records for both largest overall horse and tallest horse at various times.