Rachel and Margaret McMillan created an open-air nursery in Deptford, London that has influenced early years education for 100 years. Their vision for young children living in poverty and deprivation to have access to fresh air through outdoor learning, nutritious meals, and an enriching environment to explore and develop has been embraced and interpreted internationally since its inception. This article explores the founding of the nursery, the ethos behind the practice, and the influence the open-air nursery has had on contemporary early years practice in England.