Shal Tul was a Federation colony, populated largely by Trill.
History and specifics[]
Shal Tul was the home of Bethan Roa and Duhan Vos. In the year 2371, after being discharged from Gheryzan Hospital, Verad left Trill to take a job on Shal Tul. (DS9 - The Lives of Dax short story: "Reflections")