The Celestial Halls
The Celestial Realm is perceived as a grand manse. The Manse of the Celestial Realm is, as far as anyone knows, made infinite by the creator. Though infinite, there are landmarks and distinct rooms. The Host of Heaven reaches these rooms in many ways. The will of the traveler determines the route of travel in the Manse. The realm being infinite, one may have as much privacy or as little as one desires for contemplation.
The Grand Hall
The Grand Hall is a large space that grows to offer even more space as needed. Its vaulted ceilings show the firmament of heaven. In the Grand Hall, all of the spheres come together. Only a few times in all of celestial history has the entirety of the infinite Host gathered in the Grand Hall. Its walls are gold-veined marble. The room is arrayed in vast steps so that all can see the Primarchs when they speak. It is in the hallways around the Grand Hall that the Eternal War of Shadows rages. Shades endlessly seek the expanse of, the Grand Hall, though none are sure why the Shades do so. Many of the Shades also seek the locked doors in the Hall of Doors, seeking...something. Not even the Hall of Whispers has yet to yield the answer to the purpose of this War. Some Celestials believe that only one with the knowledge the Manse could so evade the Hall of Whispers.
The Garden
The Garden is a showcase of the creator's beauty in the world. There are trees, birds, and plants in perfect and beautiful order. It is said that all paths in the celestial realm lead to the garden. This is true in a way, but the garden will sometimes block paths to it. The ways in which it blocks travel are unknown to most celestials. Some say it does so by the will of the Primarchs; others think it does so only at the command of still greater powers. Whatever the reason, the Garden is a place for the Host to remind themselves of the perfect beauty in creation. Many go there to reflect and meditate on the purpose for which they were created.
The Hall of Doors
The Hall of Doors is a place of traveling. The hall is seemingly infinite. It has doors on either side, all the way down its length. These doors open to many places inside the celestial realm and beyond. Many of the doors are locked. The doors that are locked can be opened with the right key, but the keys are known only to some. There are some doors for which no one has a key.
The Library
The Library is a collection place of all books. Any book created in the mortal realm can be found here. The Library is often filled with celestials looking for tomes on subjects of interest to them. The Library is for all, though the books may never leave. There is a section set aside for the Primarchs alone, where forbidden texts are kept. Any knowledge that is deemed corrupting by its nature appears in that section alone, never to be read. It is the duty of the Primarchs to determine the nature of the books, and it is by their declaration that knowledge is deemed forbidden or corrupt. The books in the library cannot be destroyed so long as any copy of the text exists in the mortal realm. Most Celestials believe that knowledge should be preserved, if only so that the chance exists to overcome the temptation of forbidden knowledge. Without temptation, there can be no purity of will. Many Celestials write books as well, and treatises on many subjects fill the Library, with the Library holding the only copies. The cultures of humanity comprise a large number of books, should a Celestial which to pursue knowledge of the mortal realm, though most do not.
The Hall of Whispers
The Hall of Whispers is a dark and low stone hall, with winding and confusing turns. The hall is a place of deep shadows where many secrets can be heard. If a celestial knows how, they may find any secret ever told in the mortal realm or the Realms Above. It might take moments or a thousand years, and even skilled listeners cannot predict this accurately. The Primarch Valanya has made it her life's work to find secrets here. The need for the Second Descent was first discovered here.
The Heart of the Storm
There is a room that winds into a stair. At the top of the stair, one steps into an eternal tempest. It is here, in the Heart of the Storm, that those who pursue that Realm gain their power. It is said that all storms are born here. The spiraling wind and rain are not for the faint of heart. A mortal would be torn to pieces in the maelstrom, but some celestials retreat here to find peace.
The Hall of Wisdom
Celestial free will leads to different views of the world. In the Hall of Wisdom those ideas are tested in debate. The Celestial Spheres and Philosophies differ greatly on some subtle aspects of the Light of Heaven's plan and his works. Debates on aesthetics and the nature of mortal corruption will go on for centuries in this place. The Tharamonian Mirei in particular frequent this place. It is not so much their place, but it appeals to their reasoning minds and purpose.
The many halls of the celestial realm are often found by seeming accident, perhaps guided by their creator's purpose. Many times a Celestial going about their duties turns a corner to find themself in the Garden, or in the Hall of Doors. The legendary Light Celestial Oriset once found himself brought to the Hall of Whispers while training someone to fight. The Manse creates rooms as needed. As one seeks a place, if it did not exist and it can exist, it will exist in the halls of the Celestial Realms. The attempts to catalog or control the Manse have always failed, and it continues to have secrets for those who have existed there since the dawn of creation.