Radha Hall is where the government of Etria resides. All the exploring guilds must be approved by the government before being allowed to venture the labyrinth.
This is where the player receives official missions, as well as browse the Monstrous Codex and the Item Compendium. Everything in the Monstrous Codex and the Item Compendium must be found out by the player and reported manually to Subaltern Quinn. The discoveries are reported the next time you browse the respective database.