The Azure Blades is a fleet-based Chapter, and as such has no homeworld to return to nor a permanent Fortress-Monastery to serve as a base of operations and a repository of its precious gene-seed. The Chapter’s fleet-bound nature affords it the ability to react quickly to calls for aid, and the mobility required for making preemptive strikes against the enemies of the Imperium. In addition to this, it also allows the Azure Blades a greater variety of recruits to draw from, given the varied worlds the fleet encounters along its astral wanderings at the edge of Imperial space. However this also makes the Chapter extremely vulnerable to the all too-real dangers of Warp Travel, which had seen countless Astartes ships (and indeed, entire Astartes Chapters, like the ill-fated Fire Hawks) disappear into its depths, never to return.
In preparation for such an event, the Chapter had built several well-hidden and heavily fortified repositories of arms , relics and, most importantly, gene-seed along the fleet’s ancient route. The knowledge of the locations of these fortresses, called the Safeholds, is closely-guarded by the Azure Blades’ Librarians; while the coordinates of specific Safeholds are known by each Brother-Captain, it is said that only the current Chapter Master truly knows the location of every Safehold, and only through the auspices of the Chapter’s Librarius.
The Safeholds played an important part in bringing the Chapter back from the brink of dissolution in the wake of the Shattering, with their gene-seed stores making up for the gene-seed the retreating Chapter had been forced to reluctantly abandon in its escape from the trap the Alpha Legion had sprung. Since that time the Apothecaries of the Azure Blades have gradually replaced the gene-seed stores used, just in case the Chapter needs to recover from near-crippling losses in the future.