The Romans when making any kind of castra or fort , whether it was a regular marching camp or a winter camp followed a basic plan. Each camp would usually have four gates. The main gate (as shown here) faced the enemy. The main gate would be the one most heavily defended. Each gate was fortified with towers. Here I have placed an extra tower in the gate way. All the gates guarded a road way which lead to the camps praetorium or commander's headquarters in the center of the camp.

A typical camp would have at least two towers at each gate. A camp with four gates (perhaps gateways might be a better term) would have eight towers built for the camp. Remember that number. The gates provided the only entrance into the camp and these entrances have no physical gates. Instead the Romans would block the entrances with units of soldiers called maniples. Such guard duty would be done on a rotating schedule. Each cohort would have three maniples. Cicero's men were so pressed that they did errect a sod wall to block up the gate ways. I chose not to show this.

The island with the wall that stands before the gateway is called a tulmus. It is created by digging up sod from the ground. The sods were carefully cut being something like a brick in shape. Like bricks the sods were laid to form the rampart. In fact the entire camp's walls are built of sod. The removal of sod from the ground around the camp created a ditch. Another obstacle the enemy would have to deal with. These practices would be used by most armies well into modern times.

Atop the tulmus was a wicker wall covered with mud. This mud would protect the wall from fire and provide cover for the men on the rampart. The tulmus would stop the rush of any assault parties from the enemy. There were several different types but I am lazy so I used the most common and simple type. The Roman gate guard could defend the tulmus' rampart and a maniple would stand in the opennings on either side of it. Behind the tulmus were the gate towers and the camps's main rampart and walls. These could provide support to the guarding units.