Walking the stairs is not something difficult to do for a human, but can you imagine the struggle for a horse? Yeah, it is not as easy for a horse but the love for food and more specifically referring to the video, sweets is the right motivation.
Judging by my personal experience but also by the comments, a lot of people have tried to such a thing with their horses but they were really scared to climb the stairs. The main problem is the equilibrium which is difficult to be maintained while walking the stairs.
After all, it is not something necessary for a horse to know because stairs were cleared designed for humans and human anatomy, but it is still interesting to watch because it is something that it is not been seen before. Maybe I have missed something on the internet, but I have never watched a horse climb the stairs.
If you do know other horses who can do that, please feel free to share their video with us. If you really think about it, it is actually not a good thing because Lefty, the horse in the video can easily enter the house now and make a whole mess inside. Do you think this video is impressive? If yes, make sure to share it with your friends so they can enjoy it as well.