Fort Fontana is a 17th-century island fortress in El Este that Admiral Benítez uses as the FND navy's command base. You raid it in the mission Harpoon.
An island fortress off Sierra Perdida, built by the Spanish to keep pirates in check. The FND navy now runs its command from here, and Admiral Aña Benítez keeps her office inside.
The anti-aircraft site guarding the fort makes flying in a bad idea. Approach by water, and expect heavy resistance since the fort is the navy's headquarters.
A plaque calls a direct attack unlikely. A prisoner register inside lists guerrillas marked for torture and execution. One of the game's unique items is hidden in Benítez's office.
El Este
El Este is Yara's eastern region, a wild stretch of jungle and mountains. It is where you recruit the Legends of '67 and La Moral, and Admiral Benítez and Sean McKay hold it for the regime.
Anti-Aircraft Site Lambda
Anti-Aircraft Site Lambda is an FND flak post in Sierra Perdida, El Este. It is out on the Lágrimas Islands, so plan a boat trip rather than a flight to reach it. Destroying it also gets you Depleted Uranium.
Anti-Aircraft Site Psi
Anti-Aircraft Site Psi is an FND flak post in Sierra Perdida, El Este. It protects Fort Fontana, so knocking it out first makes any air approach on the fort far safer. Destroying it also gets you Depleted Uranium.
Anti-Aircraft Site Theta
Anti-Aircraft Site Theta is an FND flak post in Sierra Perdida, El Este. It stands in Savannah Fields, close to the Biovida Research Facility. Destroying it also gets you Depleted Uranium.