Most accounts of hauntings from eyewitnesses revolve around dark, shadowy figures that take human form. These forms often include gray ladies, monks, and soldiers, but as animals are so woven into our lives and human history, they also sometimes appear as ghosts.

There are famous reports of the ghost of a monkey at Carew Castle in Wales, and even the Tower of London is haunted by the ghost of a bear.

One of the animals most commonly seen as ghosts are horses. They are often seen on the sites of battlefields, pulling ghostly carriages or even with a headless horseman on their back. In some cases, the horse and the rider died together, but this is not always the case.

The reason horses are so commonly seen as ghosts could be because they're just one of a handful of animals to have achieved a level of sentience that makes them capable of manifesting...