By Mike Markowitz for CoinWeek …..
ROMANS WERE PROUD of their bridges, some of the most spectacular feats of ancient engineering. The high priest of the Roman state religion was called the Pontifex Maximus–literally the “supreme bridge-builder”–a title later adopted by the Popes of the Roman Catholic Church.
A number of Roman coins depict bridges, but not always accurately; die engravers were not architectural draftsmen and they struggled to represent long, complex structures in the narrow circular confines of a coin.
For most bridges, Romans relied on the same circular stone arch used to build the aqueducts that brought water into the city. Possibly the earliest coin showing such a structure is a silver denarius issued by a mint official named L. Marcius Philippus in 52 BCE. On the reverse, he commemorates his ancestor, Q. Marcius Rex, who constructed the aqueduct known as the Aqua Marcia in 144-140 BCE. What appears to be a man riding a horse across a bridge on the reverse is actually an equestrian statue of this builder atop the aqueduct. The coin is relatively common; different dies show different numbers of arches.
Emperor Caesar son of the divine Nerva, Trajan Augustus, Germanicus, Pontifex Maximus, invested for the fourth time as Tribune, Father of the Fatherland, Consul for the third time, excavating mountain rocks and using wood beams has made this road.
— Dedication plaque of Trajan’s Bridge
By far the most famous Roman bridge to appear on a coin is the Danube River bridge built by Emperor Trajan in 103–105 CE for his conquest of Dacia, north of the river. Designed by the famed Apollodorus of Damascus, it was 1,135 meters (3,724 ft.) long. Twenty massive stone and concrete piers joined by timber arches carried the roadway 19 meters (62 feet) above the surface of the river.
The bridge appears on three different denominations struck c. 107-110: a sestertius, a dupondius and an as. The coins only show one arch of the bridge, and the engraver misunderstood the structure–it seems to be a two-storied covered bridge. Modern reconstructions assume the roadway was level and open–topped, supported by radially braced double wooden arches. The massive towers topped by statuary at each end are probably correct; such towers made it easier to defend the bridge against attackers.
Trajan’s bridge remained intact for only a few years. About 117, Hadrian ordered the timber arches dismantled to prevent Dacians from crossing to the south bank.
Some of the piers remain in place underwater (two were dynamited in 1906 to widen the navigation channel, others were swept away over the centuries). The ruins of the towers at either end are preserved as archaeological sites by Serbia and Romania, respectively.
Considering how important the Tiber River has been in Rome’s history, it’s surprising how rarely it appears on the coinage. The reverse of a very rare bronze medallion of Antoninus Pius (ruled 138-161) shows two arches of the Pons Cestius, which connected the Tiber island to the opposite bank. Much rebuilt over the centuries, this bridge still exists. In a 2011 New York auction an example of this large medallion sold for $9,500.
Marcus Aurelius’ Pontoon Bridge
When a crossing was needed quickly, Roman military engineers constructed pontoon bridges, linking anchored boats with wooden planks and framing. A sestertius of Marcus Aurelius struck ca. 171-172 shows the emperor leading legionary troops across such a bridge over the Danube. There are only three boats, and they are tiny compared to the soldiers, but the engraver managed to fit the story onto the coin. An example of this rare type brought over $1,700 in a recent European auction.
In 208, Septimius Severus issued a gold aureus and a bronze as showing a bridge very similar to the one on Trajan’s coins – a braced arch between towers. What seems to be an arched roof over five tiny soldiers may be the engraver’s attempt to represent the wooden balustrade on the upstream side of the roadway. One theory (Reed) is that this is the bridge over the Firth of Forth constructed for Severus’s campaign in Scotland. A more recent argument (Desnier) is that this is the Pons Milvius, just outside Rome (see below for another representation of this famous bridge).
The aureus is so rare I could not find an illustration, but an example of the as sold for over $4,500 in a 2015 European auction.
Some Provincial Bridges
The bronze coins issued by Greek-speaking cities in the Roman East often show local landmarks, including bridges.
Adrianople (now Edirne in the European part of Turkey) is located on the Maritsa River. In 2014, an apparently unique Roman provincial bronze coin of Gordian III (238-244) sold for almost $6,700 in a major European auction. The richly detailed reverse shows the emperor on horseback with troops marching over a triple-arched bridge, while boats emerge through the arches below.
The city of Alexandria Troas was located on the Aegean near the site of ancient Troy. A bronze of Maximinus I (235-238) shows a chariot driving across a single-arched bridge, perhaps over the local Scamander River. Although rather worn, an example of this rare type sold for $745 in a 2008 online auction.
The Maiandros River (now the Büyük Menderes in Turkey) gave its name to the verb “meander”, meaning to wind back and forth. During the reign of Gallienus (253-268) a small town on this river, Antiochia ad Maeandrum, issued a large bronze coin showing a five-arched bridge beneath an image of the local river god. River gods are usually shown in ancient art reclining and holding a reed.
Mopsuestia was a city located on the Pyramus River (now the Ceyhan) in Cilicia. A five-arched bridge appears on the reverse of a local bronze coin dated to 255 or 256 during the reign of the emperor Valerian. Within the arches are Greek letters spelling out the word dorea, meaning “gift”. The reclining river god appears in the field above. Remarkably, this bridge, which has at least nine arches, still exists. A superb example of this type sold for $2,750 in a 2011 auction.
Constantine’s Milvian Bridge
To mark the foundation of Constantinople as a new imperial capital in 330, Constantine I issued an enormous volume of bronze coins in many different types, most of which are quite common today. The most affordable Roman coin showing a bridge is Constantine’s Milvian bridge type, commemorating the battle fought on 28 October 312 that secured his control over the empire.
A particularly sharp example sold for over $400 in a recent European auction.
On most examples, the representation of the bridge is very sketchy – a straight span connecting two towers, with some wavy lines below to suggest the flow of the river. The first bridge over the Tiber at this site was built in 206 BCE, and it was rebuilt many times over the centuries. The present structure, still in use, consists of five stone arches.
Modern Bridges on Coins
The impulse to commemorate bridges on coins is something modern Americans and Europeans share with ancient Romans.
A 1936 US commemorative half-dollar celebrates the opening of the San Francisco-Oakland Bay Bridge with a striking Art Deco style reverse. The 2001 Rhode Island state quarter shows the Pell Bridge over Narragansett Bay, and the 2005 West Virginia quarter shows the spectacular New River Gorge Bridge. Between 2004 and 2007 the reverse designs of the UK one-pound coin depicted famous British bridges.
It might also be noted that the reverses of Euro banknotes depict bridges from different historical eras — the five Euro note shows a Roman aqueduct modeled after the Pont du Gard near Nimes, France.
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 The dupondius was worth half a sestertius; the as was one quarter.
 New York Sale XXV. 5 January 2011. Lot 185
 Bertolami Fine Arts – ACR Auctions, E-Auction 32. 11 January 2016. Lot 819
 Numismatica Ars Classica Auction 87. 8 October 2015. Lot 293
 Numismatica Ars Classica Auction 78. 26 May 2014. Lot 1080
 Classical Numismatic Group, Electronic Auction 188. 28 May 2008. Lot 231
 Classical Numismatic Group Auction 88. 14 September 2011. Lot 985
 Gitbud & Naumann Auction 16. 4 May 2014. Lot 1174
Desnier, J.-L. “On the bridge on a coin of Septimius Severus AD 208”, Numismatic Chronicle 157 (1997)
Foss, Clive. Roman Historical Coins. London (1990)
Hallett, Judith. “Over Troubled Waters: The Meaning of the Title Pontifex”, Transactions and Proceedings of the American Philological Association 101 (1970)
Hyde, Walter. “Trajan’s Danube Road and Bridge”, The Classical Weekly 18 (1924)
O’Connor, Colin. Roman Bridges. Cambridge (1993)
Reed, Nicholas. “The Scottish Campaigns of Septimius Severus”, Proceedings of the Society of Antiquaries of Scotland 107 (1975-6)
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