Multiple initiatives within the U.S. Army are looking at radical changes for future simulation. Efforts include considering new architectures, leveraging cloud technologies, enabling point of need training, incorporating commercial technologies and data, and minimizing development and sustainment costs. Synthetic Natural Environments (SNE)… the virtual world surrounding simulation entities …represent a number of special challenges and opportunities in this sea of change. This paper presents interim results from the Multi-Resolution Environment Services (MRES) effort, which is conducting analysis, developing use cases, and executing experiments addressing the future of SNE. This paper discusses challenges with the conceptual SNE required to enable possible future simulation approaches, and examines new domains of SNE such as megacities. Traditional areas of weakness are presented with an eye toward how to address these in the future, such as simulation of weather effects. Solutions to these challenges are considered, including techniques to provide multi-resolution, composable services and data based upon simulation need and context. In progress experiments using the Program Executive Office Simulation Training and Instrumentation (PEO STRI), Project Manager Integrated Training Environment (PM ITE’s) Live- Synthetic Training, Test & Evaluation Infrastructure Architecture (LS TTE IA) framework will also be discussed.