The Austro-Hungarian army made Pula and its surrounding an impenetrable area during its rule, at least in terms of the open sea attack, having erected the defensive system with numerous fortresses, forts, batteries. One of the most interesting is the Maria Luisa fortress on Muzil.

This peninsula has an excellent geostrategic value due to its position from which the entire Pula Bay as well as the southern Brankoras Bay are simultaneously controlled. It has been the military estate during the last 150 years. The Maria Luisa fortress is a round structure, open for public from 2007. It is considered one of the biggest of the type. There is an extremely intriguing legend connected with Muzil and the Brijuni Islands saying that the fortress is connected with Brijuni by an undersea tunnel. In view of its recent availability for public visits, the fortress and its secrets are yet to be discovered.