I've been to that monument. Both as a child being dragged, and when I dragged my my children. (It's not as fun as the St. Louis Arch.)

There's a law that prevents any buildings in the area from being taller. This means when you look out you can actually compare what you see to the pictures, and drawings they have presented of the timeline. Last time I paid attention to it there was damage from the Madrid fault line quake. ( lower Mississippi River area) The earthquake cracked it, and something kept going wrong so repairs were taking a long time.

Edit : This is important for The Susquanna Alchemy Theory. ( larger and area involved than DC, but same land magic)