Trajan's Bridge

{{short description|Roman segmental arch bridge over the lower Danube}}

{{Infobox bridge | bridge_name = Trajan's Bridge | native_name = {{Langx|la|Pons Traiani}}<br />{{Langx|ro|Podul lui Traian}}<br />{{Langx|sr|Трајанов мост}} / ''Trajanov most'' | native_name_lang = | image = Trajan's Bridge Across the Danube, Modern Reconstruction.jpg | image_size = 250px | alt = An artist's interpretation of Trajan's Bridge depicted upon a light brown surface, with bridge stretching from near shore of river on the bottom left and the far shore in the top right. | caption = Artistic reconstruction (1907) | official_name = | other_name = | carries = | crosses = Danube | locale = Drobeta-Turnu Severin (Romania), Kladovo (Serbia) | owner = | maint = | id = | architect = Apollodorus of Damascus | designer = | engineering = | design = | material = Wood, stone | length = {{convert|1135|m|ft|abbr=on}} | width = {{convert|15|m|ft|abbr=on}} | height = {{convert|19|m|ft|abbr=on}} | mainspan = | spans = 20 masonry pillars | pierswater = | load = | clearance = | below = | life = | builder = | fabricator = | begin = 103 AD | complete = 105 AD | cost = | open = | inaugurated = | toll = | traffic = | preceded = | followed = | heritage = Historic Monument (Romania)<br>Monuments of Culture of Exceptional Importance, and Archaeological Sites of Exceptional Importance (Serbia) | collapsed = Superstructure destroyed by Aurelian around 270 AD | closed = | replaces = | map_image = | map_alt = | map_width = | coordinates = {{coord|44.623769|22.66705|display=inline,title|type:landmark_region:RO}} | references = | extra = | embedded = {{Designation list | embed = yes | designation1 = Serbia | designation1_type= Archeological Site of Exceptional Importance | designation1_offname = Pontes with Trajan's Bridge | designation1_date = 28 March 1981 | designation1_number =AN 44<ref>{{Cite web|url=https://nasledje.gov.rs/index.cfm/spomenici/pregled_spomenika?spomenik_id=43868|title=Информациони систем непокретних културних добара|archive-url=https://web.archive.org/web/20200609081530/https://nasledje.gov.rs/index.cfm/spomenici/pregled_spomenika?spomenik_id=43868|archive-date=9 June 2020}}</ref> | designation2 = Romania | designation2_offname = Podul lui Traian | designation2_date = 2004 | designation2_number = MH-I-m-A-10047.04<ref>{{Cite web|url=https://www.cultura.ro/sectiuni/Patrimoniu/Monumente/lista/mehedinti.pdf|title=Lista Monumentelor Istorice 2004 {{!}} Județul Mehedinți|archive-url=https://web.archive.org/web/20060827144555/https://www.cultura.ro/sectiuni/Patrimoniu/Monumente/lista/mehedinti.pdf|archive-date=27 August 2006}}</ref>}} }}

'''Trajan's Bridge''' ({{langx|ro|Podul lui Traian}}; {{langx|sr|Трајанов мост|translit=Trajanov most}}), also called '''Bridge of Apollodorus over the Danube''', was a Roman segmental arch bridge, on the modern Serbian - Romanian border, the first bridge to be built over the lower Danube and considered one of the greatest achievements in Roman architecture. Though it was functional for only 165 years, it is often considered to have been the longest arch bridge in both total span and length for more than 1,000 years.<ref>The bridge seems to have been surpassed in length by another Roman bridge across the Danube, Constantine's Bridge, a little-known structure whose length is given at 2,437 m ({{harvnb|Tudor|1974b|p=139}}; {{harvnb|Galliazzo|1994|p=319}}). In China, the 6th century single-span Anji Bridge had a comparable span of {{convert|123|feet|m|disp=or}}.</ref>

The bridge was completed in 105 AD and designed by Emperor Trajan's architect Apollodorus of Damascus before the Second Dacian War to allow Roman troops to cross the river.<ref>{{Cite journal |last=Griggs Jr. |first=Francis E. |title=Trajan's Bridge: The World's First Long-Span Wooden Bridge |url=https://www.bscesjournal.org/wp-content/uploads/CEP-Vol-22-No-1-02.pdf |journal=Civil Engineering Practice}}</ref> Fragmentary ruins of the bridge's piers are still in existence. {{stack|thumb|300px|Trajan's Bridge northern bank}}

== Site == {{See also|Drobeta (castra)|Iron Gates}} thumb|Forts on the Danube near Drobeta [[File:Remains of the Trajan's Bridge on the right bank of Danube, Serbia (27251575447).jpg|thumb|250px|Remains of Trajan's Bridge on the south bank of the River Danube, Serbia]] [[File:072 Conrad Cichorius, Die Reliefs der Traianssäule, Tafel LXXII (Ausschnitt 01).jpg|thumb|250px|Relief of the bridge on Trajan's Column showing the unusually flat segmental arches on high-rising concrete piers; in the foreground emperor Trajan sacrificing by the Danube]]

The bridge was situated east of the Iron Gates, near the present-day cities of Drobeta-Turnu Severin in Romania and Kladovo in Serbia. Its construction was ordered by the Emperor Trajan as a supply route for the Roman legions fighting in Dacia.

Construction of the bridge was part of a wider project, which included the digging of side canals so that whitewater rapids could be avoided to make the Danube safer for navigation enabling an effective river fleet, a string of defense posts and development of the intelligence service on the border.<ref>Šašel J. Trajan’s Canal at the Iron Gate. Journal of Roman Studies. 1973;63:80-85. doi:10.2307/299167</ref>

The remains of the embankment which protected the area during the construction of the canal (in a loop to the south of the Danube){{Citation needed|date=September 2025}} show the magnitude of the works. The {{convert|3.2|km|abbr=on}} long canal bypassed the problematic section of the river in an arch-like style.<ref name=Politika/> Former canals eventually filled with sand, and empty shells are regularly found in the ground.<ref name=magazin/>

All these works, especially the bridge, served the purpose of preparing for the Roman invasion of Dacia, which ended with Roman victory in 106 AD. The effect of finally defeating the Dacians and acquiring their gold mines was so great that Roman games celebrating the conquest lasted for 123 days, with 10,000 gladiators engaging in fights and 11,000 wild animals being killed during that period.<ref name=Politika/>

The bridge was {{convert|1135|m|ft|abbr=on}} long (the Danube is now {{convert|800|m|ft|abbr=on}} wide in that area), {{convert|15|m|ft|abbr=on}} wide, and {{convert|19|m|ft|abbr=on}} high, measured from the surface of the river. At each end was a Roman fort so that crossing the bridge was only possible through the camps.

On the south bank, at the modern village of Kostol near Kladovo, the Pontes fort was built in 103, concurrently with the bridge, occupying several hectares. Remnants of the {{convert|40|m|abbr=on}} long castrum with thick ramparts are still visible today. A ''vicus'' (civilian settlement) grew up around it later. A bronze head of Emperor Trajan has been discovered in Pontes, part of a statue which was erected at the bridge entrance and is today kept in the National Museum in Belgrade.

On the north bank is the Drobeta fort. It also had a bronze statue of Trajan.<ref name=magazin>{{ cite news | author = Slobodan T. Petrović | title = Стубови Трајановог моста | trans-title = Pillars of the Trajan's Bridge | newspaper = Politika-Magazin, No. 1068 | pages = 22–23 | language = sr | date = 18 March 2018 }}</ref>

==Design and construction==

Apollodorus used wooden arches, each spanning {{convert|38|m|ft|abbr=on}}, set on twenty masonry pillars made of bricks, mortar, and pozzolana cement.<ref>The earliest identified Roman caisson construction was at Cosa, a small Roman colony north of Rome, where similar caissons formed a breakwater as early as the 2nd century BC: ''International Handbook of Underwater Archaeology'', 2002.</ref><ref>Fernández Troyano, Leonardo, "Bridge Engineering - A Global Perspective", Thomas Telford Publishing, 2003</ref> It was built unusually quickly (between 103 and 105), employing the construction of a wooden caisson for each pier.<ref>In the first century BC, Roman engineers had employed wooden caissons in constructing the Herodian harbour at Caesarea Maritima: Carol V. Ruppe, Jane F. Barstad, eds. ''International Handbook of Underwater Archaeology'', 2002, "Caesarea" pp505f.</ref>

Apollodorus applied the technique of river flow relocation, using the principles set by Thales of Miletus some six centuries beforehand. Engineers waited for a low water level to dig a canal, west of the modern downtown of Kladovo. The water was redirected {{convert|2|km|abbr=on}} downstream from the construction site, through the lowland of {{ill|Ključ region|sr|Ključ (oblast)}}, to the location of the modern village of Mala Vrbica. Wooden pillars were driven into the river bed in a rectangular layout, which served as the foundation for the supporting piers, which were coated with clay. The hollow piers were filled with stones held together by mortar, while from the outside they were built around with Roman bricks. The bricks can still be found around the village of Kostol, retaining the same physical properties that they had 2 millennia ago. The piers were {{convert|44.46|m|abbr=on}} tall, {{convert|17.78|m|abbr=on}} wide and {{convert|50.38|m|abbr=on}} apart.<ref name=Politika>{{Citation | author = Ranko Jakovljević | title = Srećniji od Avgusta, bolji of Trajana | newspaper = Politika-Kulturni dodatak | page = 05 | language = sr | date = 9 September 2017 }}</ref> It is considered today that the bridge construction was assembled on the land and then installed on the pillars. A mitigating circumstance was that the year the relocating canals were dug was very dry and the water level was quite low. The river bed was almost completely drained when the foundation of the pillars began. There were 20 pillars in total in an interval of {{convert|50|m|abbr=on}}. Oak wood was used and the bridge was high enough to allow ship transport on the Danube.<ref name=magazin/>

The bricks also have a historical value, as the members of the Roman legions and cohorts which participated in the construction of the bridge carved the names of their units into the bricks. Thus, it is known that work was done by the legions of IV Flavia Felix, VII Claudia, V Macedonica and XIII Gemina and the cohorts of I Cretum, II Hispanorum, III Brittonum and I Antiochensium.<ref name=Politika/>

== Destruction and remains ==

[[File:Piciorul Podului lui Traian, malul românesc (19 august 2009).jpg|thumb|upright|The ruins in 2009, surrounded by a square concrete compound which was built to protect the monument from the rise of the water level following the construction of the Iron Gate II dam, Romania]]

The wooden superstructure of the bridge was dismantled by Trajan's successor, Hadrian, presumably in order to protect the empire from barbarian invasions from the north.<ref>{{Citation|last=Opper|first=Thorsten|title=Hadrian: Empire and Conflict|publisher=Harvard University Press|year=2008|isbn=9780674030954|page=[https://archive.org/details/hadrianempirecon0000oppe/page/67 67]|url-access=registration|url=https://archive.org/details/hadrianempirecon0000oppe/page/67}}</ref> The superstructure was destroyed by fire.<ref name=magazin/>

The remains of the bridge reappeared in 1858 when the level of the Danube hit a record low due to the extensive drought.<ref name=magazin/> The twenty pillars were still visible.

In 1906, the Commission of the Danube decided to destroy two of the pillars that were obstructing navigation.

In 1932, there were 16 pillars remaining underwater, but in 1982 only 12 were mapped by archaeologists; the other four had probably been swept away by water. Only the entrance pillars are now visible on either bank of the Danube,<ref>[http://ipsnews.net/interna.asp?idnews=20822 Romans Rise from the Waters] {{webarchive|url=https://web.archive.org/web/20061205023835/http://ipsnews.net/interna.asp?idnews=20822 |date=2006-12-05 }}</ref> one in Romania and one in Serbia.<ref name=magazin/>

In 1979, Trajan's Bridge was added to the ''Monument of Culture of Exceptional Importance'', and in 1983 on ''Archaeological Sites of Exceptional Importance'' list, and by that it is protected by the Republic of Serbia.

Trajan's Bridge is listed as a ''Historic Monument of Romania'' since 2004 under the LMI code MH-I-m-A-10047.04.

== References == {{Reflist}}

== Further reading == * {{Citation | last1 = Bancila | first1 = Radu | last2 = Teodorescu | first2 = Dragos | year = 1998 | contribution = Die römischen Brücken am unteren Lauf der Donau | editor-last = Zilch | editor-first = K. | editor2-last = Albrecht | editor2-first = G. | editor3-last = Swaczyna | editor3-first = A. |display-editors = 3 | editor4-last = Weber | editor4-first = J. | title = Entwurf, Bau und Unterhaltung von Brücken im Donauraum | series = 3. Internationale Donaubrückenkonferenz, 29–30 October | pages = 401–409 | publication-place = Regensburg }} * {{Citation | last = Galliazzo | first = Vittorio | title = I ponti romani. Catalogo generale | volume = 2 | year = 1994 | publisher = Edizioni Canova | location = Treviso | isbn = 88-85066-66-6 | pages = 320–324 (No. 646) }} * {{Citation | last = Griggs | first = Francis E. | title = Trajan's Bridge: The World's First Long-Span Wooden Bridge | journal = Civil Engineering Practice | volume = 22 | issue = 1 | pages = 19–50 | year = 2007 | issn = 0886-9685 }} * {{Citation | last = Gušić | first = Sima | year = 1996 | contribution = Traian's Bridge. A Contribution towards its Reconstruction | editor-last = Petrović | editor-first = Petar | title = Roman Limes on the Middle and Lower Danube | series = Cahiers des Portes de Fer | volume = 2 | pages = 259–261 | publication-place = Belgrade }} * {{Citation | last = O'Connor | first = Colin | title = Roman Bridges | publisher = Cambridge University Press | year = 1993 | pages = 142–145 (No. T13), 171 | isbn = 0-521-39326-4 }} * {{Citation | doi = 10.1111/j.1095-9270.2008.00216.x | last = Serban | first = Marko | title = Trajan's Bridge over the Danube | journal = The International Journal of Nautical Archaeology | volume = 38 | issue = 2 | pages = 331–342 | year = 2009 | bibcode = 2009IJNAr..38..331S | s2cid = 110708933 }} * {{Citation | last = Tudor | first = D. | contribution = Le pont de Trajan à Drobeta-Turnu Severin | title = Les ponts romains du Bas-Danube | series = Bibliotheca Historica Romaniae Études | publisher = Editura Academiei Republicii Socialiste România | place = Bucharest | volume = 51 | year = 1974a | pages = 47–134 }} * {{Citation | last = Tudor | first = D. | contribution = Le pont de Constantin le Grand à Celei | title = Les ponts romains du Bas-Danube | series = Bibliotheca Historica Romaniae Études | publisher = Editura Academiei Republicii Socialiste România | place = Bucharest | volume = 51 | year = 1974b | pages = 135–166 }} * {{Citation | last = Ulrich | first = Roger B. | title = Roman Woodworking | publisher = Yale University Press | year = 2007 | pages = 104–107 | isbn = 978-0-300-10341-0 }} * {{Citation | last1 = Vučković | first1 = Dejan | last2 = Mihajlović | first2 = Dragan | last3 = Karović | first3 = Gordana | title = Trajan's Bridge on the Danube. The Current Results of Underwater Archaeological Research | journal = Istros | issue = 14 | year = 2007 | pages = 119–130 }} * {{cite web|author=Ранко Јаковљевић|year=2009|title=Трајанов мост код Кладова|publisher=Rastko|url=http://www.rastko.rs/istorija/delo/13195}}

== External links == {{Commons category|Trajan's Bridge}} * [https://vimeo.com/52953688 Trajan's Bridge - 3D Animation] * [http://www.nonesuchexpeditions.com/nonesuch-features/Lost%20Danube/trajan%27s%20road/trajans%20road.htm Lost in the Danube - Trajan's Road] * {{Structurae|id=20001271|title=Bridge of Apollodorus over the Danube}} * [https://web.archive.org/web/20061205023835/http://ipsnews.net/interna.asp?idnews=20822 Romans Rise from the Waters] – Excavations * [http://www.rastko.rs/rastko/delo/13195 Trajan's bridge near Kladovo] (Serbian) * [http://www.aquaetarchaeologia.org.rs/cp/125 Gallery 2003] * [http://www.aquaetarchaeologia.org.rs/cp/127 Gallery 2005]

{{Crossings navbox | structure = Bridges/Dams | place = Danube | bridge = Trajan's Bridge | upstream = Iron Gate I | downstream = Iron Gate II<br />Ostrovul Mare Bridge }} {{Roman bridges|state=collapsed}}

Category:Bridges completed in the 2nd century Category:Bridges over the Danube Category:Bridges in Romania Category:Bridges in Serbia Category:Roman segmental arch bridges Category:Deck arch bridges Category:Demolished bridges Category:Drobeta-Turnu Severin Category:Ancient Roman buildings and structures in Serbia Category:Archaeological Sites of Exceptional Importance Category:Historic monuments in Mehedinți County Category:Timok Valley Category:Roman Dacia Category:103 Category:105 Category:Trajan Category:Buildings and structures in Mehedinți County Category:Demolished buildings and structures in Serbia Category:Buildings and structures demolished in the 3rd century Category:Demolished buildings and structures in Romania