repeatedly stress the sling's advantage of range. The sling was light to carry and cheap to produce; ammunition in the form of stones was readily available and often to be found near the site of battle. The ranges the sling could achieve with moulded lead sling-bullets was surpassed only by the strong composite bow. Caches of sling ammunition have been found at the sites of Iron Age hill forts of Europe; some 22,000 sling stones were found at Maiden Castle, Dorset. It is proposed that Iron Age hill forts of Europe were designed to maximize the effective defence by slingers. The hilltop location of the wooden forts would have given the defending slingers the advantage of range over the attackers, and multiple concentric ramparts, each higher than the other, would allow a large number of men to create a hailstorm of stone. Consistent with this, it has been noted that defences are generally narrow where the natural slope is steep, and wider where the slope is more gradual. Construction A classic sling is braided from non-elastic material. The traditional materials are flax, hemp or wool. Slings by Balearic islanders were said to be made from a rush. Flax and hemp resist rotting, but wool is softer and more comfortable. Polyester is often used for modern slings, because it does not rot or stretch and is soft and free of splinters. Braided cords are used in preference to twisted rope, as a braid resists twisting when stretched. This improves accuracy. The overall length of a sling can vary. A slinger may have slings of different lengths. A longer sling is used when greater range is required. A length of about is typical. At the centre of the sling, a cradle or pouch is constructed. This may be formed by making a wide braid from the same material as the cords or by inserting a piece of a different material such as leather. The cradle is typically diamond shaped (although some take the form of a net), and will fold around the projectile in use. Some cradles have a hole or slit that allows the material to wrap around the projectile slightly, thereby holding it more securely. At the end of one cord (called the retention cord) a finger-loop is formed. At the end of the other cord (the release cord), it is a common practice to form a knot or a