Zeta Site was an area on LV-1201 following Weyland-Yutani establishing a base of operations on the planet. This area actually consisted of several ruins with the original being a Pilot installation that contained the Artifact Chamber. Built around this temple was a Xenomorph Hive that were repelled by the effects of The Artifact.
Around 500 years ago, a Yautja hunting party arrived on the world in order to find worthy prey. During this time, a hunter discovered the Pilot ruins and learnt of the power of the Artifact. This led to his clan establishing a hunting lodge that was safe from the Xenomorphs and allowed them to hunt the creatures. However, at some point, the Artifact shutdown allowing the Xenomorphs to attack the Yautja base until the stasis chambers were reactivated.
The ruins of the Yautja hunting camp and the Pilot chamber remained undisturbed for centuries until the arrival of Weyland-Yutani. They designated the area as Zeta Site and placed a guard post as an entry means into the Xenomorph hive. The Iron Bears dispatched Major Dunya with infiltrating the area and retrieving the Artifact and upon the successful completion of her mission she reported to General Rykov the presence of another alien installation separate from the Pilots. This confirmed Rykov that the Yautja had visited the planet before in the past.