Another example of early Middle Ages Castle building (10th Century onward), a Turret was a small tower that extended vertically from a primary defensive tower top. They served as an extended defensive position for troops to engage advancing enemies as well as for observation. Often, many different forms of tops were incorporated (depending on the Country or region of origin). Crenellated, Open or completely Enclosed tops can be seen. Squared or rounded, various designs also incorporated wooden reinforcements to serve at additional forms of protection. Turrets were over extensions of a defensive tower, as opposed to a continuous component. Often, Turrets were supported by Corbels. Although iconic in The Medieval Castle building, Turrets (and Turreting), can be traced back to Ancient Rome, Greece and other "Pre-Classical" civilizations.