A prototype of the Xindi superweapon is deployed in the Calindra system
The Calindra system is a G-type star system located inside the Delphic Expanse. It contained six planets and over a hundred moons.
In the early 2150s, the Xindi used the system as a testing area for the prototypes of the Xindi superweapon. Because the system was secluded and uninhabited, it made a perfect location for the testing of the sensitive weaponry.
Because of the highly destructive nature of the weapons that were tested, the Calindra system was dominated by vast fields of debris and planetary rubble, the remains of the moons and asteroids that were used as targets for the weapon tests. There were also large fields of radiation left over from the high-energy weapons. Jonathan Archer likened the system to the Bikini Atoll on Earth.
In December of 2153, the Enterprise NX-01 discovered the tests proceeding in the system, thanks to sabotage committed by Gralik Durr to a shipment of kemocite. In cooperation with the Andorian warship Kumari, the Enterprise launched an assault on the superweapon prototype, and the Kumari managed to escape with the weapon in its cargo bay. (ENT: "Proving Ground")
Enterprise returned there several days later where they encountered Degra's ship. After overpowering his ship, they took Degra and his two aides prisoner, and after an elaborate charade, were able to extract from Degra the location of the weapon building site, Azati Prime. Thereafter they released Degra to his ship and left the system to locate the weapon site. (ENT: "Stratagem")