Thule is a small star station orbiting Ross 248 (a.k.a. Gliese 905), an M6 class variable red dwarf 10.3 light years from Sol. In the authors' original timeline, Thule was founded in 2072 by ECS8 Gloriana to support sublight trade, departing from Venture Station (Kruger 60, 4.5 light years distant) in 2067. As the seventh of the "Hinder Stars" stations, Thule was made obsolete by discovery of FTL.
Nonetheless, the novel Finity's End reveals that Thule occupies a key position in Alliance-Union history, as the location of the first resistance to Earth's imposition of trade visas by the merchanter starship Finity's End. As much as Union's eventual declaration of independence, this was the casus belli of what became the Company War.
During the sublight era, Thule was part of a trading network including Venture, Galileo (EV Lacertae, 6.5 light years distant), Bryant's (61 Cygni, 6.9 light years distant), and Olympus (Groombridge 34, 1.8 light years distant).
Thule is 10.6 light years from Eldorado (UV Ceti/Luyten 726-8), 12.2 light years from Pell (Tau Ceti), and 9.5 light years from Mariner (Van Maanen's Star), but the latter is not founded until 2175.
Although sublight trade among the four star stations around Bryant's continued for over a century after the founding of Pell, even before the discovery of FTL, the rich development from Pell to Cyteen had led this group of star stations to question their future viability. The abandonment of Glory and Alpha Stations only increased the concern, as a flood of colonists first arrived with their fears and then continued up the line to a perceived promised land.
By 2230, the discontent had crossed a threshold. When ECS8 Gloriana called again that year, Thule leadership requested and received transport to Venture in order to have their grievances heard. The discontent among the four stations only grew, ultimately leading to the collapse of the remaining Hinder Star stations during the Company War.
Thule was reopened by the Alliance following the Company War. It was rendered obsolete a second time with the discovery of a point mass off Bryant's Star, called Gaia Point, which created a more direct route to Earth from the Beyond.
The novel Rimrunners describes Thule as a dim double star, but no companion has ever been detected.
From Thule, direct FTL routes exist to Venture, Bryant's, and Eldorado (UV Ceti, 10.6 light years distant), i.e. with no intermediate jump point. However, the long jump from Thule to Eldorado would only be possible for a military ship or a lightly-loaded merchant with powerful engines.