Environmental education (EE) is instrumental in developing environmentally literate citizens with the knowledge, attitudes, and skills necessary to support sustainable development. In the case of EE school field trips in the USA, these experiences also foster learning and skill development that supports meeting state and national educational standards. However, despite the importance of EE field trip programs, not all schools participate. This study explored the barriers to accessibility to EE field trips by conducting semi-structured interviews with EE providers and administrators of middle schools in the Congaree Biosphere Reserve (CBR), South Carolina, USA. We also used geospatial information systems to investigate accessibility spatially. Results suggest that aspatial barriers such as curricular constraints, capacity to plan and lead field trips, costs, and transportation influence participation. The results also suggest that these aspatial barriers are often interlinked and that access to EE field trips is disproportionately allocated to students in private education and urban settings and that rural, poor, minority, underperforming, and English as Second Language students face additional hurdles. We discuss a range of potential solutions to overcoming these barriers that reduce participation in EE field trips in the CBR.