The settlement of Heusden, bordering on the river Meuse (Maas), as we know it today dates back to the 13th century, and started with the construction of a fortification to replace the castle that was destroyed by the Duke of Brabant in 1202. This fortification was quickly expanded with water works and a donjon (castle keep). The city of Heusden received city rights in 1318. The castle of Heusden was the property of successive dukes of Brabant, in 1357 it went over to the counts of Holland.
With the construction of ramparts and moats the castle became located within the city's fortifications, and the castle lost its function as a stronghold. The donjon was now used as a munition depot. A disaster marked the end of the castle of Heusden and caused the economic demise of the city; on 24 July 1680 a terrible thunderstorm hit Heusden, and lightning struck the donjon. Sixty thousand pounds of gunpowder and other ammunition exploded, and destroyed the castle. It took the people of Heusden seven weeks to clear the rubble and debris. The castle was never fully rebuilt. However, the original outlines of the main features were restored in 1987.
References:The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.