Only the location of Corandolis is never revealed. As the location of the other Towers are known and can be connected with a certain Domain, an educated guess about the location of Corandolis can be made; Elhalyn had Hali right at the lakeshore, Neskaya is less than a day from both Serrais and Armida, Tramontana is close to Caer Donn, Dalereuth is close to Valeron and thus serves Aillard, and both the Comyn Tower and Arilinn would be accessible from the various points of the Hastur Domain. Which leaves Ardais alone without access to a Tower, thus we can guess that Corandolis Tower is in the Hellers somewhere beyond Scaravel about a day from Ardais. Of the location of the remaining two unnamed Towers we have no knowledge.