Someone had left these outside the door of a house so I was able to get a good picture. There was a big animal with four legs and a tail tied up nearby eating grass.

They're leather boots with metal bits on the heels for horse riding.

The reason they were outside the house is that in the culture of these particular Earthlings, footwear is considered to be unclean so you leave your boots outside the door.

Actually, it's a good job the owner didn't catch you interfering with them because they probably belonged to a Bedouin horseman!