Cubby house
My dad had a big wood pile in the front corner of the yard, I would gather wood from it and build my cubby houses they never stayed I would have to pull them apart at the end of the day but I would have rooms and a proper floor plan. I spent hours in these little structures by myself making up stories about family and friends all living the ideal life in my little wooden structures. Then I would put the wood back and climb the pile and watch the world go by on the other side of the fence. I was so good I was very sad when my dad declared the wood pile dangerous and we had to take it to the tip, I remember crying for ages but that's life.