ByRoute

The ByRoutes are an ancient series of traditional interstellar transit pathways used by the Counter Xarctic Traders and numbered according to some long lost scheme which has never been satisfactorily explained. They pre-date the Society Of Contemporary Races. Indeed, the origin of all these routes is so ancient that the waypoint stars have drifted significantly in their courses since the first ships traversed their length. As civilisations and species have come and gone whilst the routes persist, the purpose and relative significance of each route has undoubtably changed enormously over time.
All of the known routes that enter the Bubble and wind through it, also leave it without coming to a stop at either end.
The solar system is a way point on ByRoute 17 which leaves the Bubble heading roughly towards the core of the galaxy in one direction and towards the rim in the other. Earth has long been a system of interest to the wider galactic community and that must have been true even before the Society of Contemporary Races. The Counter Xarctic Traders claim that they made occasional scientific landings but no more than that.
Routes referenced so far in the stories on this site include the following:-

ByRoute	Notes
17	Includes Earth. Passes through the Bubble in a roughly radial direction.
18	Includes the Nezah System with the twin worlds of Mainstream and Greenlush, and Allanon II, passing close to the Hequidar System at this point.
32	Route 32 never enters the Bubble. It starts at Querequia and heads across the Querequian Fall in the direction of the galactic core, entering the Jyncotax Halo at the Tekovess system, the site of a famous battle in the Cata-Zin Catastrophe.
45	Passes close to the Darquin double star system and the planet of Helldrone
74	A route on which the Counter Xarctic Traders recovered wreckage in 3471 from the 2985 Trolene VII expedition into the Forbidden Regions