Location-based games have been around since 2000 across various fields, including education, health, and entertainment. The main challenge facing such games is content generation. In contrast to normal games, content in location-based games is inherently dependent on location. The biggest challenge is the availability of the content globally. Other challenges include player engagement, enjoyable interactions with the real-world environment, safety, and customizability based on player performance and preference. While crowdsourcing has often been adopted as a tool for content creation, this approach requires quality control. Designing high-quality content requires detailed guidelines. In this paper, we introduce design principles for the creation of high-quality content that can survive for long periods of time. These principles are derived from ten years of experience running our in-house orienteering treasure-hunt game called O-Mopsi , which represents a case study in this paper. O-Mopsi allows players to visit pre-defined locations. The design principles are expected to be generalizable to other location-based games as well as to the creation of sightseeing tours more generally.