The Silvestri Trace was originally a small, lightly traveled, and all together insignificant hyperspace route, originating from Sullust. When the Galactic Empire chose the Forest Moon of Endor as the site of construction for its second Death Star, the Silvestri Trace was expanded and lengthened to reach the moon. This was done via the use of non-mass S-thread boosters planted in hyperspace and then by moving realspace debris along its length. The hyperlane was then renamed the Sanctuary Pipeline.