Quote Originally Posted by GameRant
Reddit user Chicken_Vomit_ discovered that the markings on the walls of the Astral Observatory have a significant meaning. This deep pit is the stage for the first stage of Link's fight against Calamity Ganon, so players are likely disoriented. It turns out the markings reflect what lies outside of the castle in each direction, including a variety of landmarks like the Great Plateau, the Divine Beasts, and more. This room can only be explored via the use of an exploit, as Link normally couldn't enter this room without triggering the battle.

As comments on the video point out, there are some major implications tied to these markings. Namely, the markings are clearly from Hyrule's ancient Sheikah tribe, who should not have known where the Divine Beasts would end up in the future. In spite of this, the markings match Hyrule exactly as it exists in the game's present-day. This serves to reinforce that the events of Breath of the Wild were prophesied far in advance, and Zelda was not fated to receive the power of the Triforce of Wisdom until Hyrule fell.

Of course, this isn't the only indication that the Sheikah tribe anticipated Link's quest in Breath of the Wild. Every Shrine was created for Link's sake, thousands of years in advance. Still, it serves to raise questions about the role of destiny versus agency in the Legend of Zelda series. This is particularly true since Hyrule Warriors: Age of Calamity uses time travel to substantially alter the course of history, allowing Hyrule to prevail against Calamity Ganon a century before Breath of the Wild.
Zelda: Breath of the Wild Player Finds Interesting Detail in Final Boss Room