In Assassin's Creed Valhalla, you may come across Rigsogur Fragments, which are a type of collectibles in the game. On this page of the guide, you will learn where to find the collectible and how to reach it. This will make it easier for you to complete the Cent region in 100%.
The sixth page can be found in Centerbury.
The fragment is located in the building, on the upper floor. You can reach it by climbing the column. You shouldn't be bothered by any opponents - obtaining the treasure will be easy. Simply pass the dusted ledges and you will reach a desk in the right corner of the room.