This is a comment I posted to u/John_Demonsbane’s post in r/DestinyLore and I wanted to share it here. He tackles GF: Cayde-6 and the date 126 years, and whether or not we should compress most of the significant events that occurred in City history into a hundred years.
If we take the three years each of major Destiny installment (vanilla, 2014; TTK, 2015; ROI, 2016) and subtract them off of Cayde’s date, seeing as it is “in-game” years", we have 123 years.
Now we take Ghost’s comment of the lift not being used in over four hundred years; we must note that he meant not only rhe Dark Age but also the City Age, since it was abandoned when the Collapse occured, and no one would have maitained it or used it.
Finally, going back to my point about the major installments, if the Traveler arrived in the “present day” as noted in the opening cinematic of “A Guardian Rises” and take it to mean the 21st century, or aka 2014, then from this we can get a rough estimate:
*Present Day – 2014 (21st century)
*Golden Age – 300 years (between 21st and 24th; extrapolated)
*Dark Age – 300 (24th and (27th; extrapolated)
*City Age – 100 (27th-28th; extrapolated)
*In-game time – three RL years
You get that magical Bungie number 7, as in 700. (More precisely, 2740 if you add 2014 + 600 + 126 – and don’t forget that even technically we’re in the year 2000, due to the AD dating system it is actually the 21st, so same priciple applies here) Also, I think the City Age and the Dark Age bled into one another, as it is noted there’s confusion as to when it began exactly, so Ghost’s comment about 400 years makes more sense in context.