Roman camp (singular castrum Romanum, castra romana, castra Romanorum – “Roman camp”) was characterized by excellent performance. What is worth emphasizing was not built by professional engineers and builders, but by ordinary legionaries. The main building material was wood. The camp was created during the campaign every day.
It seems certain that the legionaries were undergoing special training to practice the construction of such a camp. If necessary, they had to be able to set it up quickly and efficiently. Proof of the existence of training camps is the remains of such facilities in western Germany (North Rhine-Westphalia state). According to ancient sources, the average time for erecting a Roman camp was between 4 and 5 hours. In favourable conditions, it could be erected even in 3 hours.
The fortified Roman camp was either square or rectangular, surrounded by a wall with four gates and a rampart or palisade. Corners of castrum were rounded to make it difficult for enemies to climb the palisade. The camp, which was the seat of legionaries during the winter, was referred to as hiberna.
The Romans had certainly built fortified camps during the war with Pyrrhus in 280-275 BCE. They were smashed every night to shelter the army in the event of a lost battle or leaving rolling stock and wounded during the battle.
Construction usually began in the afternoon, because the army’s daily timetable was arranged by the hour. Very early in the morning (when the sun rose) the legionaries set off. The journey took 8 hours on average. A special group was sent in front to choose the best place to build the camp and begin preparations for construction. After a constant march, the legionaries stopped in a convenient place for the camp and divided into groups:
- bringing wood and building material
- material storage and transport to the site
- patrolling and protecting the workplace
As Vegetius, a late Roman writer points out, the construction of the camp was extremely important.
Recruits are to be instructed in the manner of entrenching camps, there being no part of discipline so necessary and useful as this. For in a camp, well chosen and entrenched, the troops both day and night lie secure within their works, even though in view of the enemy.
– Vegetius, De Re Militari
Establishment of the camp
According to Polybius, the place for the camp was chosen by tribunes and centurions. First, the location for the command tent was marked out; then straight lines were drawn around this tent, which marked out the space on which the tents of the tribunes would stand, and then of the legion. Distances were carefully measured and marked on the ground with flags of different colours. When the main forces arrived at the site, the soldiers had a clear view of the layout of the camp and construction work began.
When the commander stopped and work began on the camp, auxiliary units were sent to plunder the area (enemy territory) or to obtain food, feed and wood for bonfires. Legionaries extracted tools from their backpacks and built a fortified camp. It is worth noting that the most frequently chosen place for the creation of the camp were hills, for defensive and scenic reasons. In addition, the camp should be located facing the slope, if possible close to the forest and water source – minimizing the possibility of an ambush. The area was cleaned and levelled.
When the legionaries dug the ground, one cohort from each legion stood guard. The rampart near the moat was built from the soil recovered in this way. The embankment is usually measured, as described by Polybius, usually 4 meters high and 1 meter wide, and equal to 4 meters wide and 3 meters deep. Julius Caesar reportedly had a penchant for embankments over 6 meters wide.
Construction began with defensive elements. Cut-down trees were used for gates (about 15 meters wide) and watchtowers, which, after being constructed on-site, were placed on each of the four embankments (all of them were to be burnt the next day when the army set off on the road). The firing forces were located along with the forecast. The space of 60 meters between ramparts (agger) and the first rows of tents were filled with cattle, booty and prisoners of war. It was a so-called intervallum. As Polybius writes, they were placed here so that in the event of an enemy attack one could not reach them with fiery arrows. This space protected leather and canvas tents and wooden buildings against enemy shots and attempted to set the camp on fire during the siege. Thus, the embankment (agger) was built and a palisade (vallum) was built, which together with the excavation (fossa) surrounding them surrounded the whole camp. intervallum was left between the camp ramp and the soldiers’ tents.
The height of the camp wall was usually two-thirds of the width of the ditch, the width was similar. The slope and wall surrounding the camp were always crowned with a palisade (vallum).
1 – forum
2 – Via Praetoria – Praetorian Street
3 – Via Principalis – main street
4 – Porta Principalis Dextra – right gate
5 – Porta Praetoria – main gate
6 – Porta Principalis Sinistra – left main gate
7 – Porta Decumana – rear gate
Along with the construction of fortifications and defensive barriers, at the same time the headquarters of the army commander (pretorium) and then the quarters of his deputies, including the chief of staff, were built. Then tents of tribunes and centurions were created, each of which had its own tent. The next ones were repair workshops, the quartermaster’s area was fenced and a camp square or forum (locus gromae) was marked out, located in the centre of the camp. At the forum, there was a sacrificial altar, rostrum and the mentioned tents of the commander and officers.
Then the legionaries marked the streets. Each cohort had its own street. In the Roman camp, two main streets were distinguished: Via Principalis and Via Pretoria, crossing at a right angle. At their ends were the gates:
- Main Gate (porta praetoria)
- Rear Gate (porta decumana)
- right gate on Via Pricncipalis (porta principalis dextra)
- left gate on Via Pricncipalis (porta principalis sinistra)
Along the streets, rows of ten-man tents were arranged according to a template unchanged for centuries. They were originally made of leather, but as early as the 1st century BCE they were commonly sewn from the canvas. If it was raining during the construction of castra, then the tents were set up earlier. It is worth noting that all the tents were carried during the march by the mules. Camps erected during the winter were a bit more comfortable because the tents were replaced by small huts. After several months of apprenticeship, legionaries could now set up camp with their eyes closed.
During all this work, the legionary was allowed to put down his shield and javelin, as well as remove the pack from his back and helmet, but besides, he had to wear a leather jacket with sewn-in armour plates, a sword and a dagger so that he could rush to fight without a moment’s delay. Noticing the lack of any of these items of weaponry was punishable by death. So you can see that the legionary’s life was not very interesting and comfortable. Any small oversight or non-discipline was severely punished.
When the camp was ready, a certain number of guards went to designated positions on the ramparts. The sentries were placed every 10 meters on average. The changing of the guard was announced by the sound of a trumpet, which was administered every three hours. Guard posts at night were patrolled by four-horse groups who reported. If someone overslept or fell asleep on duty, they were threatened with punishments up to execution. It can be concluded that the life of the legionary was very hard and based on strict discipline. One could not afford error and mistake. All the legionary’s misdeeds were severely punished.
To measure the night watch (vigiliae), the Romans used a water clock called hourglass.
Types of camps
Four types of Roman camps were commonly distinguished:
- Castra aestiva – a marching camp, it was always built of wood and had a rectangular appearance. The gate was often abandoned, which was replaced by a break in the fortifications. Established for each night during the summer campaign, surrounded by a ditch, earth embankment and a palisade built of wooden, sharpened from both ends of the piles, brought by legionaries from the previous camp as part of the equipment, called pilum muralis. All constructions were burned or dismantled when the legionaries left the camp. Marching camps were built in 3 to 6 hours. Construction and layout were presented earlier.
- Castra navalia – a camp built on the shore for the protection of ships offshore.
- Castra hiberna – the camp established for the winter, surrounded by wooden and earth defensive structures, had gates and watchtowers. The tents were protected against cold and rain by skin and straw or replaced by wooden barracks.
- Castra stativa – a permanent camp established in strategic places, strongly fortified, with brick defensive structures. Depending on their size, they had devices typical of cities; valetudinarium (military hospitals) or infirmary, warehouses, stables, shops and even thermal baths. On the borders of the Roman Empire, a network of camps, smaller fortresses (castelli) and observation towers connected by Roman roads formed defensive systems called limesami. These camps were built of stone. They had the form of a fortress.
Often, the rectangular form was abandoned, especially in late antiquity, when any height ground was used to increase defence. Great emphasis was placed on measuring the space of the camp, which had to take into account the terrain, water supply and the number of legionaries to be stationed there. The planning of all types of facilities began with determining the centre and directions in which the camp was oriented. Permanent camps were the basis for the emergence of later cities.
Beginnings of cities
Permanent camps located during the empire on limes with time began to transform into cities. It was mainly caused by the transfer of frightened residents of border villages to camps, which in time became lively settlements. Settlements canabae were created at this type of camps, which often turned into cities gradually. It is also worth noting that many people displaced from their homes under the imperial edict had to move to camps. In turn, Roman soldiers stationed for years in the camp started families, which also affected the transformation of the military camp into a defensive settlement, and then a city.
The newly created cities, surrounded by walls, took the form of a rectangle or square (like camps) and had two main streets crossing the city into quarters:
- Cardo (north-south)
- Decumanus (east-west)
There were many other smaller roads at right angles to these streets.
The focal point of each city at the intersection of Cardo and Decumanus was the forum around which the temples, curia, and basilicas were built. The sheer proximity of the legions guaranteed security and stimulated the development of cities that became important European metropolises in the following eras.
The remains of castra Romana gave rise to cities such as Cologne, Vienna, Paris and Reims. Also, the names of some British cities show that they were established on the site of Roman fortified camps (Chester, Chichester, Gloucester, Manchester).
Appointment of the permanent legion camp
- Porta decumana – back gate of the camp;
- Porta praetoria – front gate of the camp;
- Porta principalis dextra, porta principalis sinistra – side gates of the camp, right and left.
- Via decumana – one of the main roads, starting at the back gate, running to the centre of the camp until via quintana (perpendicular to it);
- Via praetoria – one of the main roads of the camp, running from the front gate (porta praetoria) up to the door of the headquarters (Principia);
- Via principalis – one of the main roads of the camp, connecting both side gates (porta principalis dextra et sinistra), necessarily running perpendicularly to via pretoria and via decumana;
- Via quintana – the road parallel to via principalis, did not connect to any of the gates;
- Via sagularis – a road leading around the camp, from the inside of the fortifications through the so-called intervallum (space between ramparts and camp buildings).
Individual roads divided the camp into three basic parts
- Praetendura – front part, extending from Porta Praetoria to Via principalis, most often occupied by legionary barracks
- Latera praetori – located in the middle of the Roman camps, limited by Via principalis and Via quintana;
- Retendura – starting with Via quintana and continuing to Porta decumana.
- Praetorium – the commander-in-chief’s headquarters, located in close proximity to the headquarters;
- Domus – tribune’s quarters, extending in series called scamnum tribunorum. Usually located in a pretend along Via principalis;
- Centuriae – barracks in which the legionaries were quartered, grouped in characteristic rows. Individual contubernias were allocated quarters consisting of two rooms: armament externally located, place where weapons were kept; and internally located papilio – a bedroom, with the same name as the Roman military tent. 12-14 such double rooms, lying next to each other formed a kind of pavilion in which soldiers of one century lived. 1/3 of its surface was where the centurion was, and maybe optio and other junior officers. The remaining 2/3 were occupied by rank and file legionaries. Six such pavilions, located parallel to each other, formed the cohort’s quarters.
- Principia – headquarters, always in the middle of the camp. In its centre was a courtyard surrounded by colonnades (basilica principiorum);
- Aedes – the main chapel, in which legionary insignia, among others, was stored, located in the central part of principia, surrounding the courtyard. The main treasury (aerarium) was often located in its floor. In this chapel stood statues of gods and divine emperors, and altars on which sacrifices were made;
- Armamentaria – armories, included in the principia, surrounding the central courtyard;
- Officia – offices located at the back principia, one of them – tabularium legionis – was the place where all soldiers were registered;
- Scholae – near the office of the room where various soldiers’ associations met (collegia);
- Fabricae – legionary workshops in which military equipment was repaired, most often located in retendura;
- Valetudinaria – camp hospital, some medicines were also produced here, located in a pretend or latera Pretoria;
- Horrea – granaries;
- Thermae – a bath complex with identical parts as in classic Roman baths and a swimming pool (natatio) and a covered exercise place (basilica thermarum.)