The Ducha'asa Vell system is a star system located in the Kalandra sector. During the Dominion War the system became a Dominion stronghold. Several outposts were located in the system including the Bethra Nor space station. It was liberated after a week long siege by the Starfleet Seventh Fleet and Klingon forces. (The Dominion War Sourcebook: The Fires of Armageddon)