Horse boot with cupped sole

A horse boot has a sole that includes a dome portion designed to conform to the frog and sole of a horse's hoof when no pressure is exerted on it. The dome provides a support surface for the frog and hoof sole when the boot is off the ground and it resiliently deforms downward, thereby allowing the frog and hoof sole to deform naturally, when the boot presses against the ground. As a result, the hoof's frog and sole are always supported in resilient manner while allowed to move as needed for their natural function. The pressure exerted by the ground against the edges of the sole of the boot and the simultaneous counter-pressure exerted by the hoof cause the dome in the boot's sole to flatten, thereby slightly increasing its size to accommodate the natural deformation of the hoof.