That is awesome! I would have loved to have done that back in the day. We did have an absolutely huge hay barn though and we made some pretty cool forts in there with tunnels and what not. The hay barn was big enough to park a decent sized plane in it. And it was half full of square bales. Good times.
That snow fort will be dangerous come warmer weather though. They will have to make sure to tear it down so neighborhood kids don't play in it when it starts melting.