Staying on my horse until its dead, I found this in the t4 Psionic institute book ( no, I haven't read it, don't know if its any good, I do however have two copies, let me know if you are interested...)
Shig(Massilia/0510)
This high population world has built its culture around psionics. One of its inland lakes has the curious property of interacting with the psionic powers of those who go beneath its surface. The first time a person with psionic potential immerses himself in it , his powers are unlocked....pilgrimagaes to the lake are required of every citizen upon reaching adulthood...
in the latter part of the 3I , Shig is Cluseret. With its rlative proximity to capital, I don't know what happened to its traditions post psionic suppression, but I bet that post virus , they would have made a come back. In any case, I don't really have a bunch of info on Massilia in the new era, I know its really close to the black curtain, but I wonder if the people turned back to their cultural traditions in the face of technology gone wild, what would emerge ?