This study explores the role of urban green spaces (UGSs) in Early Childhood Education and Care (ECEC) teachers' pedagogical practices and their impact on young children's environmental and sustainability learning. Utilizing observations, teacher interviews, conversations, and a comprehensive survey conducted in Stavanger, Norway, the study reveals the crucial role of UGSs in shaping both teachers' pedagogical practices and children's learning across various subject areas. The research highlights the educational significance of diverse UGSs in providing varied and tailored learning experiences that are crucial for children's education and development. In line with this, the study provides findings supporting the application of experiential learning theory within UGSs and ECEC settings. Additionally, the findings reveal a growing concern among teachers about the reduction of UGSs due to increasing urbanization. These results underscore the need for both teachers' advocacy and strategic policy to preserve UGSs, ensuring their availability for future generations.