On Santo Stefano there are several military areas and some others that are subject to military servitudes. We have already mentioned Saint George Fortress or anti-aircraft battery Punta Zucchero, Sugar Peak in English, with the rests of the original station built between two world wars. There exist fuel storage location Punta Sassu as well as the Italian military navy bases.

In 1972 the American military base was founded

Following the NATO agreements from 1949 and on decision of Giulio Andreotti, at those times the Italian Prime Minister, right here on Santo Stefano was granted in 1972 an area to the United States Navy to host a military support-ship to assist the nuclear-powered submarines.

25th January 2008: the Americans left

After the end of cold war, after years of protests against the presence of the support-ship and continuous accusations of radioactive contamination, however never confirmed by scientific surveys, on 25th January 2008 the United States bases was dismissed and the Americans left. Their departure left a significant vacuum in the field of economy, employment and real estate in La Maddalena which the islanders try to replace by tourism. 

On Santo Stefano island exists also a vast network of tunnels excavated on purpose in hard granite rock with a function of military hide place for munitions.