Sentinel Towers

The Sentinel Towers are part of a still-functional production facility for Precursor Sentinels. They also serve as watch post for a Precursor building housing an interplanetary portal. 
==Construction and Physical appearance==
The Towers themselves are built partly in to mountain cliffs. They are constructed of a metal resembling bronze, and glass. 
==History and Function==
The Towers were built prior to the Koozer-Ga war. Then, the Na'vi planet of Pandora was a Precursor outpost world. During the war, there was a scramble of most of the tribal population to board the Precursor's advanced spacecraft, including Keyships like Fleetrunner. The Omega clan used their technology-most of which they had co-opted from the Precursors, to shield their city. After The Rings were fired, those who were not on the Keyships headed towards The Ark or in the Omega clan's cities were killed. The Towers and the temple they protected were left at the mercy of the Pandoran jungle for 100,000 years, as none of the local tribes would go near them. The towers build and construct automated attack and defense drones known as Sentinels. They also house point defense turrets and power sources for the force-field gates protecting the Precursor Temple.