Fantasy play, or pretend play, is an integral part of childhood. While too often limited by the narrow confines of a role play area, pretend play can flourish outdoors if children are given the space and materials.
Great article by Marisa Lark Wallin at Community Playthings:
https://www.communityplaythings.co.uk/learning-library/articles/lets-play-outside?source=pal219