Under an un-polluted sky, our ancestors watched, searching for answers to the motion of the stars. Around the globe communities created various beliefs about the cosmos leading to the emergence of cultural and ideological traditions and festivals. From Stonehenge to Great Pyramid of Giza, from the Great Stupa of Sanchi to Doi Suthep Temple, monuments are aligned with their heavens, providing a reference to time and direction. Many were not built all at once on a single plan and there is there is often no record for the timing of their construction. Using reverse calculations of the sky map together with written texts that related to the concept of the monuments, one can determine the date these monuments were constructed and fill in missing pieces of the jigsaw of history. Here, I present work that has been conducted in Chiang Mai at Doi Suthep Temple. An archaeoastronomical methodology was applied to the alignment of the temple, together with a study of Lanna’s records and other scriptures, i.e. Purana Samhita and the idea that this sacred temple was established on an auspicious date in the Lanna Calendar. The results suggest that the temple orientation might relate to the acronychal rising of the constellation Corona Borealis during the 15th century CE, a time when King Mueangketklao reconstructed the present temple. This constellation is related to the Lunar Mansion, Vishakha Nakshatra. At present, there still a tradition of walking up to Doi Suthep Temple on Visakha Bucha Eve to worship Lord Buddha’s relics enshrined at the top of the Chedi.