Tunnels
Tunnel of Eupalinos, Samos, Greece. Constructed around 550-530 BC, supposedly on the order of the island's tyrant Polykrates. The tunnel is 1036 meter long and was carved into solid limestone through a mountain. The purpose of this tunnel was to connect the city of Samos with a spring which was situated just on the opposite side of a mountain.
Why was the tunnel carved through the mountain instead of going around the outside? Probably because Polykrates felt that a conspicuous aqueduct would have left the city's water supply too vulnerable to besiegers.
What makes the tunnel so special? Apart from its sheer length, this ancient tunnel is the first known in history where
two separate teams advanced from both ends of the tunnel.*1 This technique requires meticulous planning and equally meticulous excavating work, even today where it has become the standard method of constructing tunnels. It has been calculated (Tom Apostel) that a mere deviation of only 2 degrees from the ideal line would result in the two crew being at leat 30 meters apart at the proposed junction. As it was, the Greek architect Eupalinos achieved a difference of merely 60 cm in elevation at the junction of the northern and southern tunnel! Water could flow in a straight line from the source to the city reservoir through the tunnel.
Interestingly, the tunnel was first described by Herodot who praised it as one of the greatest miracles he had seen. Later, knowledge of the tunnel was apparently lost. It was only due to a re-reading of Herodot's enthusiatic praise, that the tunnel was rediscovered in the late 19th century! Today, the tunnel can be visited by non-claustrophobic tourists.
*1 The tunnel of Siloam in Jerusalem predates the Eupalinos tunnel by 200 years, but the two crews probably worked their way along an existing underground watercourse.http://en.wikipedia.org/wiki/Eupalinos (see links below, especially Tom Apostol (PDF): http://pr.caltech.edu/periodicals/EandS/articles/LXVII1/Apostol%20Feature%20(Samos).pdf)
Treadwheel Crane
Roman Crane, Reconstruction 1989, Bonn, Germany. How were the engineering feats of the Greeks and Romans possible? The invention of the crane by the Greeks at the end of the 6th century BC greatly facilitated the moving of heavy loads. The Romans eventually added the treadwheel to the crane, thus greatly multiplying its loading capabilities.
For a comparison: It has been estimated that it took 50 Egyptian workers to elevate a 2.5 t block at the Pyramids. In contrast, the biggest Roman treadwheel cranes could lift up to 6 tons with a mere two persons in the treadwheel!
This means that per person a Roman crane could lift 60 times as much as the Egyptian worker! The crane in the pic could lift in an experiment 5 tons 8 meters in the vertical and horizontal plane.
Source: Hans-Liudiger Dienel & Wolfgang Meighoerner: Der Tretradkran, Publication of the Deutsches Museum, Muenchen, p.13ff.
Triumphal Arches
Arch of Septimus Severus, Forum Romanum, Rome, Italy. 204 AD. This kind of arches were meant for purely ceremonial and propaganda purposes. As it was Roman custom, the victorious general or emperor moved through the gate, lauded and praised by the people as saviour of the nation. This arch was erected on the occasion of recent Roman victories against the Parthians.
Note the inscription above. The Roman letters still look exactly like modern capital letters - after 1800 years.
http://en.wikipedia.org/wiki/Arch_of_Septimius_Severus
Tombs
Tomb of Cecilia Metella, outside Rome. Built in the first half of the first century BC along the Via Appia it had been for eons a prime landmark for visitors coming to and from Rome. Diameter of 20 m. Later it served as fortress as still can be seen by the crenellations.
Mausoleum Hadriani, Rome, Italy. Built 135-139 AD as tomb for emperor Hadrian. Later used as papal castle and site of many sieges.
Public Toilets
Public flushing toilets, Ostia, near Rome, Italy. Probably the single most important invention since the wheel, the Romans definitely knew how to spend a good time. Remains of Roman flushing toilets have been found all over the empire, making the assumption safe that they were ubiquitous in the Roman Empire. Notably, Roman fortresses have featured them regularly, even at the very periphery of the empire (Housesteads, England; Dougga, Tunisia), making hanging out in the public toilet a favourite past-time of legionaries and auxiliaries alike.
Hypocaustum
Caldarium from the Roman Baths at Bath, England.
Workings of a Hypocaustum. Largely self-explanatory. The trick was to lead the hot air from the fire site in such a way as to enable as much contact as possible with both the floor and the walls. Hypocaust work at a very high degree of efficiency, with 90% and more. They are real floor heatings, a feature seen not even today in most modern households.
After the invention of blowing glass in the first century AD, some caldarium already featured even double glazed glass windows!
Aqueducts
Segovia, Spain. Built around the turn of the first to the second century AD. Maximum height 28.5 m. The aqueduct provides water for the city which is located on a plateau.
http://en.wikipedia.org/wiki/Segovia_Aqueduct
Athens, Greece. View from the Acropolis. Creative chaos.
Limes
Hadrian's Wall, northern England. The Hadrian's wall protected the northern frontier of Roman Britain against the Celti tribes in what is now Scotland. It was constructed presumbly on the personal order of Hadrian after a visit to the Isle in the 120s. The construction took about 10 years.
Looking to the casual eye more like an overdimensional garden fence, the Hadrian's wall actually constituted probably the most advanced linear border defensive system all the way until the construction of the Ming wall 1400 years later. The wall was built entirely out of (lime-)stone and extended for 117 km with an average height of 5-6 meter and a width of 2.5-3 meter. The wall was backed by 14-17 full-sized forts, each holding between 500 and 1000 auxiliaries. Besides, it featured 320 watchtowers, and 80 gates guarding at regular the space in between. In the rearside, special marching camps and even practice camps were found.
A curious thing is that the parapet, being 50 cm wide, was barely walkable. This suggests that the limes was primarily not meant to be defended from atop the wall like a common city wall. Rather, the wall must have served as backing for the stationed Roman troops. Although not perfect, it outdid other contemporary defensive system which were usually simple rammed earth affairs or at best dry stone walls with no parapet at all.
In addition to the curtain wall, the Hadrian limes also featured at its forefront a broad ditch, and at its backside a military road and the so-called vallum, that is two huge banks with a ditch between, marking the military zone.
The Hadrian Wall can only be understood as part of the overall Roman border defensive system. Among those are the Limes Arabicus alone had a length of 1500 km. In addition, several thousand kilometers of so-called river limes (Rhine and Danube) protected the northern frontier with a continuous string of watchtowers, fortlets and military ways. Also the Antonine Wall and the comprehensive defensive systems in Tunisia, Libya and Mauretania.
The Upper-Germanic limes which featured ultimately stone towers and a continous wooden palisade. The Raetian limes even a 3 meter high stone all besides the usual forts, and fortlets, watch towers, military ways and communication techniques.
All in all, the Roman limes was the most modern linear defensive system of its time and clearly outdid all other ancient border defenses, notably the
Chinese wall, not only in terms of quality, but also quantity. The Hadrian Wall,in particular probably unsurpassed in its sophistication until early modern times.
Follow the course of the Hadrian Wall: http://local.live.com/default.aspx?v=2&cp=55.013325~-2.33025&style=h&lvl=17
Greek Temples
Greek Temple at Segesta. Around 420 BC. Dorian Style. The interesting thing is that actually Segesta never was major Greek power or mercantile center. Nonetheless, its citizen were able to construct such a huge building within 10 years, which is a remarkable feat, even though the temple was for unknown reasons never completed.
VaultsThe vault is an immensely important feature of architecture. Until the 19th century the arch and vault were the only alternative to the far more limited post-and-lintel system supporting a flat or peaked beamed roof. Again, Greco-Roman architects showed great proficiency here, being the first to use huge vaults in a regular manner, and thereby laying a crucial foundation to the later construction of Christian churches and Muslim mosques.


Maxentius Basilica, Rome, Italy.What to say? Note that the surviving part actually only constitutes less than a third of the original basilica. Yep, you read right. The original basilica was more than three times as huge. This is only the remaining left
side wing...
Thermae
Aerial view of Caracalla Thermae, Italy, Rome. Constructed 212-216 AD. "The bath complex covered approximately 13 hectares (33 ac). The bath
building was 228 meters (750 ft) long, 116 meters (380 ft) wide and
38.5 meters (125 ft) estimated height, and could hold an estimated
1,600 bathers."
http://en.wikipedia.org/wiki/Baths_of_Caracalla
Mosaic floor, Caracalle Thermae, Rome, Italy. Even the chicks go crazy.
Harbours
Aerial view of Trajan's Port, near Ostia, Italy. Early 2nd century AD. The hexagonal basin was designed as an enlargement of the already enormous Claudius port (today silted) which proved to be too small in the Golden first century AD.
Plan of the Trajan Harbour. Note that it was actually the mucher smaller basin, while the earlier Claudius was equipped with a light house and huge breakwaters reaching into the sea. The enormous harbour system became necessary due to the insatiable demand of Rome for grain. Grain carriers of up to 1000 metric tons carried corn from all corners of the Mediterranean to the capital, establishing a bustling maritime trade network.
Water Mills
Remains of the Barbegal water mills. Dated now into the early 2nd century AD, the whole complex featured 16 overshot water wheels which were erected at the slope of a hill. An aqueduct brought water from a nearby river to the top of the hill, from where it entered through a rock cut gap into two mill-races with 8 overshot wheels each.
The Barbegal complex has been sometimes called the
biggest pre-industrial complex. The overall output of grinded corn had been estimated to be enough to feed the whole populace of Roman Arles with 350 g bread per day each, that is 16.000 people.
Source: Andrew Wilson: Machines, Power and the Ancient Economy, in: The Journal of Roman Studies, Vol. 92., 2002, p.12
Model of the Water Mills at Barbegal, near Arles, France. Note that the vertical overshot wheels were the most efficient way to harness water power.
The watermill was an invention of the Greeks. The first literary evidence appears in the 1st century BC, but recent scholarship by M.J. Lewis shows convincingly that the 3rd century BC is a more probable date (a passage in 3rd century BC writer Philon where he writes about various types of water mills had been mistakenly taken for a later Arab interpolation).
Stadiums
Stadium at Aphrodiasis, Asia Minor, Turkey. According to Wikipedia "it is said to be probably the best preserved of its kind in the Mediterranean." It measures 262 by 59 m. A construction date I could not find out, although I have been there once. Beautiful, still place in the midst of nature and nothing. Recommendable for its strong combination of nature and history.
Libraries
Library of Celsus, Ephesus, Turkey. 125 BC. Reconstructed facade with the ancient stones lying around. According to Wiki once place of 12.000 scrolls. The library is situated only a stone throw away from the theatre posted above.
Friezes
Pergamum Altar, Berlin, Germany. Originally from Pergamum, Turkey. Constructed in the 2nd century BC by the hellenistic kings of Pergamum, a close ally of Rome. The frieze epicts the monumental battle between the Gods and the Titans of Greek mythology.
Close shot. Strictly speaking, the Pergamum frieze does not belong to architecture, but to the art form of great sculpturing. However, the frieze was part of an altar at the Acropolis of the city.
What is so special about the frieze? It is the way how the figures are sculptured. Thus far, Near Eastern reliefs have always depicted smooth and flat figures with little profile. The Pergamum frieze however shows the Gods almost three-dimensional, almost disconnected from the frieze wall behind, thus achieving more plasticity and liveliness of the figures. AFAIK this way of sculpturing was previously unknown anywhere else and thus constitutes a genuinely new facet of stone art.
Amphitheatres
Interior view of Colosseum, Rome, Italy. Built in the 70s AD. What one can nicely see here are the underground chambers from which the wild beast and gladiators were heaved by huge wooden elevators into the arena.
Breakwaters
Breakwater at the ancient city of Samos, modern Pythagorion, Greece. Alright, here I am at a loss, because I am aware of only a single extant Greco-Roman breakwater. The mole of ancient Samos, already mentioned by Herodot in his 'Histories'. However, to be precise, only the foundation remains of ancient Greek origin, whereas the superstructure is modern.
Anyway, breakwaters were another speciality of Greco-Roman engineering, Encarta even attributes the whole invention of breakwater to the Greeks. Anyway, the dimensions were by any means huge. The mole of Alexandria, to give a single example, connected the mainland with the isle of Pharos, being
1600 meter long.
City Walls
Aurelian Walls, Rome, Italy. Constructed rather hastily during the crisis of the third century by the capable Roman emperor-general Aurelian. Before, Rome had been for centuries basically an unwalled city, sufficiently protected through the gladius of the legionary and the pax romana. The wall was 19 km long, protected by 382 towers and featured 18 city gates.
Note that the towers still do not protrude as far as is the case with medieval walls, thus limiting for archers the possibility of flanking fire. On the other hand, the walls were originally additionally protected with an extensive system of ditches (where the parking lot is now),
proteichisma called. This front end defense acted as further obstacle to siege machines and particularly to keep the walls themselves out of reach of the catapults.
http://en.wikipedia.org/wiki/Aurelian_Wall
Paved Roads
Paved Street, Pompeii, Italy. Pre 79 AD. Impeccable stone pavement. In other pics, you can see still deep grooving in the pavement, left by heavy cart use.
Crosswalk, Pompeii, Italy. Pre 79 AD. Note the strong resemblance to the cover of the Beatles album 'Abbey Road'. Roman cultural influence transcending the ages.
Via Appia, between Rome and Capua, Italy. Constructed 312 BC by the Roman censor Appius Caecus. The Romans built paved roads on an absolutely unparalled level. In terms of quantity and quality, the Roman road system was probably only matched until quite recently. Even today, quite a few countries still feature lesser road systems.
Via Domitia, southern France. 118 BC. The building of Roman roads often started as soon as a territory was conquered and 'pacified'. In the case of this road there was a span of less than 20 years after the area had been incorporated into the empire.
http://en.wikipedia.org/wiki/Roman_road
Dams
Proserpine dam, Merida, Spain. Along with the nearby dam at Cornalvo, the Proserpine dam is still in use, roughly 1900 years after its construction! The Proserpina dam is located about 10 km north of Merida and was build in the first century AD. It
is 427 m long, 12 m high and is on top 2,3 m broad. It is a earth dam covered with bricks,
has two bends in the crest and nine buttresses on the inner side of the dam. Two inlet towers
are placed on the inside of the dam construction. The water was transported to Merida through a 10 km long aqaeduct which entered the town by means of a aqueduct
bridge over the river Rio Albarregas.
Dams of the Roman Era in Spain:
http://traianus.rediris.es/textos/presas_in.htmRoof TilesCanalsFortsMinesGranaries
Edited by Gun Powder Ma - 16-Oct-2006 at 18:06