1-8 and the Rupel-Nete line as the first defence line. This plan was ratified by Act of March 30, 1906. The plan provided for the construction of 11 new forts and 12 new redoubts. This so-called Hoofdweerstandstelling included in total on the east bank of the river Scheldt 16 forts and 10 redoubts and on the west bank 5 forts and 2 redoubts. Structure of the forts and redoubts Brialmont forts Classical fortifications had an approximately rectangular shape. A good example of a rectangular fort with artillery positions on the corners is Fort Liefkenshoek of the 16th century. The gradual evolution in the fort construction in the 19th century led to two schools, the 'French' and 'German'. The German forts had a polygonal structure with caponiers. The French forts had a bastioned construction. Brialmont in 1846 visited Germany where he took notice of the German way of construction. The forts had multiple functions. They were created for long range defence, support fire between the forts and ditch and short range defence. The design was adapted to these functions. On the outside the forts were protected by 40–50 m wide ditches, which were to obstruct a direct assault. On the outside of the ditch the ground was sloping (the glacis) to enable direct fire on any enemy. On the inside of the ditch walls were raised up to 10 m height to protect the inside of the fort against direct fire. The artillery was placed on and behind the walls. The actual fort had a polygonal structure. The main building of the fort was the réduit within the fort with the quarters for the crew of the fort in peacetime and as last defence if the enemy had already penetrated within the perimeter of the fort. This réduit was manufactured in brick. It was defended by guns on the roof. The guns were placed at the outer sides of the fort. The main armament was at the front (from which the enemy was expected) behind the earthworks. This armament was placed in the main caponier (a kind of bunker with a thickness of 2.5 to 3m) in the middle of the main front. The main front had a width of about 350 m. At the sides of the main front are two half caponiers. On the main front about thirty guns and mortars for the long distance defence were placed. Both