This is what the authors of the volume “The Dacian Calendar of the Sanctuary Ensemble at Sarmisegetuza Regia” said:

“Let us turn our attention to the great circular sanctuary. The outer circle of stone consists of 104 pieces. At first glance, this number seems unusual, but if we think that it is twice the number 52, it all makes sense. 52 is the number of weeks in a year, and if we want to see how many days that year, we multiply 52 by 7 and have the answer for 364 days. So a complete rotation of the outer circle of stone in the Great Circular Sanctuary took place every two years. Then the Dacians made the necessary corrections. Why not after a year? Because it would have broken the symmetry of the perfect year. All equal months, every 28 days each, equal seasons of 13 weeks each (91 days). At least one year was to be preserved for this “perfection”, otherwise, the world was chaotic in chaos (that’s what many say about their religion and their psychology and mentalities). But why did not they make the correction after three, four, five years or more? The answer is simple – the Dacians were simple, practical, wise, and intelligent people, contrary to the opinion of historians who consider them barbarian. If it was too many years before the correction was made, the gap between the tropics and the Dacian year would have been too great. “