From Project: Redcap
Val-Negra is the original domus magna of House Flambeau. In Fifth Edition, the domus magna moved to Castra Solis. In previous editions, Val-Negra remained the domus magna of the house to the canonical start date of a saga.
Val-Negra earned the whole Chapter Nine of Faith and Flame: The Provençal Tribunal. There is also an article in Sub Rosa issue #17 that gives full details of Val-Negra as a covenant for player characters to revive from Winter to Spring.