|Map||Basic Data||Lunar Image|
|Class:||Adeptus Astartes Homeworld|
Highcastle is garrisoned chiefly by Storm Wardens, though it is also guarded by gargoyle-servitors mounted on the keep's crenelated towers. Massive chambers hold the Chapter's vehicles and wargear, where they are preserved for future battles. Inside the gray halls are many banners awaiting Chapter Heraldry to be bestowed upon them, and scars left over by the Nemesis Incident. Mechanical furnaces are found in the lower halls that run deep beneath the moon's surface, materials are provided here making it possible to create fresh weapons and vehicles. These activities are overseen by the Storm Wardens' Master of the Forge.
Beneath even these deep-found halls are the stasis chambers, which are unknown in location to all but the Chapter's Dreadnoughts. Here lies Chapter Master Owin Glendwyr, the entire original First Company and many other Storm Wardens, who rest now in stasis-slumber as a consequence of the Nemesis Incident. Much of the fortress is sealed, in keeping with Owin's final command, before he departed to his stasis vault.