There has been significant interest in the values and benefits of early childhood nature experiences on children’s well-being and development. One aspect of studying the exposure of children to nature that requires more focus is the role played by early childhood educators. In particular, there is a need for early childhood environmental education training for pre-service educators. This study will explore the use of a UNESCO Biosphere Reserve as an outdoor classroom for early childhood environmental education pre-service professionals. Exploratory quantitative and qualitative descriptive data from a series of three short surveys (pre/post/delayed post) provide a basic overview of pre-service teacher perspectives, experiences, and outcomes of an environmental education intervention. The results indicate that the participating pre-service educators had little to no familiarity with the environmental concepts or the biosphere reserve site before participation in the intervention. The post-intervention and delayed post-intervention results show that pre-service educators perceived that their understanding of the concept had improved. The results also show a perception of the positive role that biosphere reserve sites can play in early childhood education. Three critical implications emerged from the overall quantitative and qualitative results: (1) specific support should be given for early childhood environmental education training; (2) biosphere reserve functions provide support for efforts to improve connections to nature; (3) early childhood education has the potential to support the broadening of the biosphere reserve audience.