Fortifications are militaryconstructions designed for defensivewarfare. They have been used for many thousands of years, in a variety of increasingly complex designs. The practice of improving an area's defense is also known as "fortification". Many military installations are known as forts, although they are not always "fortified".
... Roman Empire. He also attacked the Schmalkaldic League in 1546 and defeated John Frederick I[?] of Saxony and imprisoned Philip of Hesse[?] in 1547. At the Diet of ...