This paper contributes to the dawning disruption of the prevailing notion of the child–nature relationship through a new materialist reading of children’s dens, and proffers a re-grounded and worldly gaze on the relationship with implications for the promotion of children’s outdoor lives. The study is an ethnographical field study among 10–12-year-old boys in a Danish school. Data were generated through participant observation, and include video recordings and photographs of children’s dens. Drawing on a flat ontology and plugging in key Ingoldian concepts of meshwork and growing (Ingold 2011a, 2013), the analysis suggests that children’s relations to dens cut across taken-for-granted subject–object binaries and go beyond common notions of nature as inert materials. I find that dens are growing in an ever-becoming meshwork comprised by human and non-human intra-actions, and that agency or vitality can be ascribed broadly to the material world. Possible implications for planning are considered.