The process of “Slighting” developed around the 11th Century. It was the purposeful destruction of a fortified structure (primarily a Castle). Long the staple of Medieval Defense, Castles and related Fortifications were designed to protect and Army, Ruler or even small Populace from Enemy attack. In this, great expenses were taken to build them. It was not normally an easy task to besiege a Castle. Large amounts of Military resources were required, and most often than not, Castles were avoided for traditional “Contests” on the Battlefield. With the advent of Gunpowder and Cannon, Castles reached their website unfortunate demise. Large Calibers of Cannon became capable of destroying Perimeter Walls as well as Interior structures. This, coupled with the Engineering tactic known as “Underminimg”, made Sieges more effective. In cases were an Enemy Castle surrendered without a Siege, thus posed a dilemma for The Victor. Often, it took resources to occupy a captured Fortification, that could best be served elsewhere. In such case, a Victorian could not leave such Fortifications standing (least they be used by an Enemy again at a later date). The time needed to dismantle a Castle or related was equally time consuming, if not impossible. Thus was “born” the process of Slighting. In practice, this involved using Gunpowder and Cannon to literally “blast” a Castle or Fortification to rumble (or at best, severely render such unusable). The process of Slighting became a main tactic during England’s Civil War Period. Many Castles were pressed into Service by Royalist Forces. Given the size and purpose of Parliamentarian Armies, Castles and Fortifications captured needed to be quickly dispatched. In many cases, these Medieval structures had been converted into the previously discussed Device and Gunpowder Fortification Systems of the 15th and 16th Centuries. These types were reinforced greatly to support Artillery, Gunpowder storage and serve as Defensive points to exploit thus new form of Warfare. Many fine examples of Ancient Castle building were thus lost due to Slighting. The practice would still continue in Warfare well into the early 20th Century, until the advent of Aircraft, made the need of Slighting, somewhat obsolete.