Running outdoors is an increasingly popular form of physical activity and has been proven to substantially reduce the risk of major chronic illnesses such as cardiovascular disease. The topic of runnability has received considerable attention but with conflicting conclusions and remaining gaps. The physical environment and its features impact running experiences. Detecting features facilitating and deterring runners is crucial to promoting this physical activity and, therefore, overall health. A scoping review of current literature was conducted to identify environmental factors conducive to running. Online databases were used to identify all articles on runnability to date; a total of one hundred and two (n = 102) papers were selected as they identified environmental correlates preferred by runners. Findings include a preference for green spaces and connecting with nature, perceptions of higher safety away from traffic congestion and pollution, and routes with wide, smooth surfaces and high connectivity. Essentially, natural surroundings are substantially more desirable than urban settings. Studies have shown that even when a running route is within an urban environment, it is usually connected to or between green spaces.