Thonis-Heracleion: finding a legendary port under the sea

Perhaps it was the tsunami in the 4th century AD or the great earthquake in the 8th century AD that hit the shores of North Africa, or perhaps the gradual erosion of the coastline. More probably, it was a combination of all three. But about 1,200 years ago, one of the greatest ports on the Mediterranean coast slipped beneath the waves. The entire city, with its monumental architecture, its colossal stone statues, and all the detritus of a bustling commercial hub, was lost to the sea, along with its name.

Until, that is, Franck Goddio and his team from the European Institute for Underwater Archaeology (IEASM), with funding from the Hilti Foundation, surveyed the area at the mouth of the Nile.

The archaeologists noticed traces of a submerged landscape about 6.5km (4 miles) off the Egyptian shore. What they had found was Thonis-Heracleion, a long-forgotten emporium that once controlled the maritime trade entering and leaving Egypt. And in doing so, they also solved an ancient mystery: historical sources mention two cities on this westernmost mouth of the Nile near the city of Canopus, where the great river enters the Mediterranean Sea: Thonis and Heracleion. In fact, they are one and the same.

Finding the city

In 2000, after several years of geophysical survey researching the ancient great port of Alexandria – Portus Magnus, home of the Pharos Lighthouse, one of the Seven Wonders of the World – the IEASM team picked up signals on their equipment a little further out in the Bay of Aboukir. These indicated strong magnetic disturbances in the centre of the eastern part of the submerged Canopic landscape: long lines of strong magnetic gradient running in parallel along an east-north-east to west-south-west direction in a part of the bay that was relatively shallow. The team took core samples of the sediment. The results suggested that the region had experienced some kind of seismic activity, either earthquakes or subsidence. Intriguingly, they also showed that this area was formerly part of a river bed. It was once made up of land and waterways in the lower basin of the Nile Delta on a main branch of the river with its secondary tributaries, where they emptied into the sea.

Franck Goddio and his divers decided to take a closer look. What they found, 5m to 8m (16-26ft) below their survey ship, poking up through the sediment on the sea floor, were the archaeological remains of huge architectural structures. These buildings ran along the same lines as those picked up by the magnetic survey, confirming earlier suspicions that the area had been affected by one or more geological catastrophes. Given the immense weight of these huge structures and the soft sediment on which they stood, it is more than likely that they contributed to the collapse of the land, which eventually sank beneath the waters. However, underwater excavation has also revealed that the city was no stranger to natural disasters: wooden posts and planking reinforcements had been used in various areas at different periods of its history to shore up the land and prevent slippage.

‘We knew from the very beginning that we would have to address the complexity of a landscape in which land and water is intermixed,’ explains Goddio. It certainly appears that the inhabitants took advantage of the natural topography, using interconnecting water channels for transportation and communication across the city. Now, 12 years on, the team is finding important new information not only about the natural features of the site, but also about the layout and organisation of the city itself, with its port and temples.

As the archaeologists began to investigate further, they discovered a number of sanctuaries. In the southern section of the site they uncovered 150m (492ft) of a wall that encircled a temenos – an enclosed sacred place with a main temple, secondary temples, and other buildings. The main temple is dedicated to the primary god of the city, Amun Gereb, the most potent Egyptian deity of this period, with the power to bestow the treasures of the universe on the new king, and with whom any pharaoh would strive to be associated. However, it was not unusual for Egyptians and Greeks to worship their own versions of the same deities, so while to the Egyptians he was known as Amun, he was revered by the Greeks as Zeus, ruler of the Olympian gods.

To the north of the temple is a shrine to Khonsu, the son of Amun. The Egyptian Khonsu equates to Heracles, son of Zeus. According to the renowned Egyptologist, Prof Jean Yoyotte (1927-2009): ‘Khonsu in the 1st millennium BC becomes popular as a saviour in distress, a warrior, and as a god who provided oracles. These qualities caused his worship to surpass that of Amun, so that foreigners could mistake the Amun sanctuary for one of Heracles.’

Certainly, Herodotus, who visited the city in about 450 BC, asserts the temple was dedicated to Heracles, who, according to the Greek writer, first set foot on Egyptian soil here. It is from this temple that the city gets its Greek name Heracleion. The Temple of Heracles, Herodotus informs us, offered the privilege of sanctuary and was where Helen of Troy with her lover Paris took refuge during their flight from Laconia. According to the 1st century BC historian Diodorus Siculus, Heracles once saved the town from flooding by turning the river back to its former course.

Finding the name

Three vital pieces of information led to the identification of the city. First, there was the discovery of a naos – a stone shrine containing the statue of the principal god venerated there – dedicated to ‘the Amun Gereb’. This reference is also found on an inscription from the Decree of Canopus, on the stele from Kom el-Hisn on the Western Delta (ancient Imau), which dates to the ninth year of the reign of Ptolemy III (247-222 BC): it mentions a nearby city with its temple of Amun Gereb but which, in the Greek version of the inscription, is translated as ‘the city of Heracleion’.

Then, the archaeologists found a gold plaque inscribed in Greek announcing that King Ptolemy III had founded (or renovated) a shrine to Heracles here. The clincher came with the discovery of an intact stele made of granodiorite in the same temenos as the naos. This stele is an almost exact duplicate of the one found in 1890 at Naukratis, the Greek commercial hub about 75km (46 miles) upriver and through which all foreign trade passed on its way into and out of Egypt’s interior. Both texts are written in traditional Egyptian, and both sanction an order made in 378 BC by Nectanebo I, the founder of the 30th (and last native) Dynasty, stating that taxes should be levied and the monies given to the temple. The two sites mentioned on the Stele of Naukratis to benefit from this levy are Naukratis itself and ‘a town called Hôné’ – i.e. Thonis – while the Thonis Stele announces that it is to be sited ‘at the mouth of the Sea of the Greeks, in the town whose name is Hôné of Sais.’ Both superbly crafted steles date to the 4th century BC, and, other than the references to their respective locations, are identical in material, size, and script.

Statues and shrines

More than 300 statuettes and amulets have been found, most dating to the Late Egyptian and the Ptolemaic periods, and including both Egyptian and Greek deities. Perhaps one of the most awe-inspiring encounters the underwater archaeologists have come across is the discovery of three gigantic statues that were found in the Pharaonic style temple of Amun Gereb. These colossal red granite figures represent a Ptolemaic pharaoh, his queen, and – perhaps the most remarkable – Hapy, a fertility god that personifies the Nile’s floods.

The statue of Hapy has no inscriptions but he is recognisable from his iconographic features: he is a plump individual with a bulging belly, just as one would expect for a fertility god. He holds a heavy offering table on which gifts would have been placed, and stands with one leg positioned slightly forward. His face is featureless, which is a typical characteristic for portrayal of gods during the Late Egyptian and early Ptolemaic periods – Hapy probably belongs to the 4th or 3rd centuries BC. On his head he sports a tripartite wig of a style normally worn by male deities. From it rises a clump of papyrus, a plant associated with Lower Egypt and with Hapy himself. His straight false beard is unusually short, though there is evidence that it had been damaged and repaired in Antiquity. In fact, the statue had been damaged and repaired more than once in the past, possibly having toppled following land subsidence or earthquakes. Usually, fertility gods appear in pairs, but no partner has yet been found for Hapy.

The two huge royal statues represent a king and a queen who would have stood on either side of the doorway to greet their subjects entering the temple. The king stands about 5m (16ft 5ins) tall, the queen about 4.9m (16ft), both Ptolemaic in style, and both with their leg positioned slightly forward.

The statues from the temples, along with the votive objects discovered in the sacred area of the temenos are revealing more about the religious world of this part of the Nile Delta. Most of the statues are from the end of the Late Egyptian period and early Ptolemaic period, c.4th–2nd century BC, but excavation has revealed that the religious practices here date back much earlier, perhaps as far as the 6th century BC. These include a variety of utensils such as braziers, lamps, situlas, and bowls in all materials from alabaster and limestone to bronze. Images and statuettes of deities depicted with such artefacts give us vital clues as to how these objects were used during religious ceremonies within the walls of the sanctuary. They were being reproduced on an extraordinary scale, both for home consumption and for export, and date mainly to the Late Egyptian and Ptolemaic periods.

A large quantity of artefacts associated with religious activities were found in a canal that linked the harbours with a lake to the west. Boats passed along here on their way to Canopus – now also submerged, about 4km (2.5 miles) west of Thonis-Heracleion. This was clearly a major ceremonial route between the two cities for religious processions, mainly in honour of Osiris.

The temenos was the pivotal point around which much of Thonis-Heracleion was organised. To the south were temples and their annexes on a central promontory overlooking the city. To the north and east stretched the harbours of a vast port, protected by a string of sand dunes, with its quays opening onto the Nile via a narrow channel. The location was ideal: it was protected both from the prevailing winds from the north-west, and from north-easterly storms.

Harbour hazards

The harbour installations are complex: there are several major port basins interconnected by tributary waterways, all centred around the temple area. The temenos is bordered by two channels crossing the city from east to west, joining the port basins on the east to a lake on the west. To the north is a wide channel called the Grand Canal, which connected the north port basins to the Nile; while a narrow waterway that ran south-west linked the river to the southern basins.

Silting was a perennial problem for all water channels, and regular maintenance was required to ensure clear access for river traffic. Another hazard was the temporary nature of sand dunes, which tended to shift – indeed, the archaeologists found evidence that links between the basins of Thonis-Heracleion and the Nile changed several times during the active life of the port.

The Egyptian shoreline around the Nile Delta was not a welcoming one for maritime traders: there were no natural harbours and its shallow waters were treacherous to coastal trade – ideal pirate and wrecker territory. The Delta was broken by so-called ‘false mouths’, which led sailors into dead-end lakes, mazes of floating islets. Shallow channels were fringed by sedges and reeds that blocked the view, and boats could easily get stuck in the soft mud beds.

Yet, despite these hazards, this was a busy port, as the wealth of artefacts attest – including a set of Athenian weights, which are the only such weights to have been recovered from an Egyptian site.

More than 700 anchors and at least 60 shipwrecks – more than any other archaeological site yet uncovered – have been identified in the port area. Most wrecks date to between the 6th and 2nd centuries BC. They are providing valuable new information not only about Egyptian ship-building techniques, but also the long reach of Egyptian seafaring and the manner of trade on the Nile at this time.

The discovery of so many stone anchors shows that this port was a hub of sea-going – as opposed to river – trade: such heavy anchors would have sunk into the soft Nile mud, but sat securely on the sandy sea floor. The anchors have a distinctive elongated cone shape with holes bored through the top through which cable was threaded, and some also had one or two holes through the lower section through which wooden stakes were pushed.

But what is particularly exciting is that many of the anchors found can actually be directly linked with the wreck to which they would have been attached when the ship was moored in the harbour.

Most of the boats are shallow-bottomed craft, or baris, suited to river traffic and the transportation of goods from the port up into Egypt’s interior. Thonis-Heracleion was the entry point on the Canopic mouth for goods imported by the Greeks, and it therefore controlled all river trade coming from the Mediterranean before heading inland up the Nile to Naukratis and then beyond. Ships were only able to venture further up the river through the two principal mouths of the Nile, that of Pelusium to the east, and of Canopus to the west.

According to Herodotus: ‘if anyone penetrated another mouth of the Nile, he had to attest that he had not come there of his own volition and, having sworn that oath, set sail in his ship to the Canopic mouth; or, if contrary winds made it impossible for him to sail in that direction, he had to transport his cargo on the local boats (baris) going across the Delta until he reached Naukratis.’

Carbon dating of wood fragments revealed that the majority of shipwrecks date from the Late Period (664-332 BC), and are therefore pre-Ptolemaic. But the biggest surprise to the archaeologists, given that this was a major port for the import and export of goods into Egypt from throughout the Mediterranean, was the discovery that almost all the boats found here were local craft.

Analyses of the wood used in the construction of the vessels discovered in Thonis-Heracleion show that most – about 70% – was acacia, a tree that is native to Egypt. Another native tree, sycamore, was also found. Four shipwrecks have planking made mostly of oak, a tree found in the region around Thebes, so also home-grown. Only two shipwrecks were made of wood that came from a non-native species: pine. David Fabre, archaeologist with IEASM, explains: ‘This is remarkable, as it suggests a marked lack of foreign ships as well as a virtual absence of imported shipbuilding timber, despite the clear references in historical texts to an import trade in this material.’

He has also examined the methods used to build these ships. Most were constructed using tenon and mortice joints, a technique well know around the Mediterranean at this time, but applied in a different way here at Thonis-Heracleion. The planks for the hull were laid flush, edge to edge, and held in place by tenons pegged into mortices in the planks. This formed a thick network, or frame, of staggered rows inside the hull, which gave it extra strength. ‘It is tempting,’ says Fabre, ‘to see this as a specifically Egyptian style of naval construction.’

This technique is actually described by Herodotus, who noted the use of acacia wood to build an Egyptian baris: ‘[they] saw into planks two cubits long, which they then assemble like bricks … they fix these planks together with long pegs very close together’ – a construction technique perfectly illustrated by the shipwrecks at Thonis-Heracleion.

These vessels were as at home on the shallow waters of the Delta as they were out to sea in the Mediterranean. This is changing our view of Mediterranean and Egyptian trade, which, perhaps, was not dominated by the Greeks and Phoencians, as commonly believed; it seems that the Egyptians were also enthusiastic and effective participants. The flat-bottomed design also ensured easy passage up the Nile as transhipment craft, taking goods unloaded at Thonis-Heracleion from abroad, and transporting them to destinations further inland.

Some of the ships were also used as permanent structures – possibly once they had served their purpose as sea-going vessels – forming part of the harbour either as quays, part of the embankment, or even as a bridge. Shipwreck 17, dated to the middle of the 4th century BC, is surrounded by 14 vertical wooden poles, securing the hull to the sea-bed, suggesting it may have been used to form a quay or an embankment. The 1st century BC historian Diodorus Siculus describes how boats were sometimes used as bridges: ‘At each mouth [of the Nile] is built a city that is divided by the river and whose two parts are separated by bridges of boats and well-sited defences.’

However, perhaps some ships experienced a more violent role in history. Around 20 wrecks similar to Shipwreck 17 lie one against the other at the entrance of a harbour basin. Could they be what remains of a last desperate attempt to defend the port of Thonis-Heracleion from Persian invaders in 343 BC? All are secured in place by wooden stakes, all have limestone rubble in their hulls, and all appear to have been scuttled. Most significantly, all are found strategically positioned at the mouth of the harbour – blocking the entrance. Whether they were effective in doing so or not, the final outcome was the same: Egypt fell to the Persians in 342 BC, and the last native pharaoh of Egypt, Nectanbo II, fled to Nubia.

However, whether these boats were part of the contrived infrastructure of the port, used in its defence, or part of a naval flotilla lost during battle, what they show us is that Thonis-Heracleion was once a thriving and vital port complex. At its heart was the temple, overseeing a network of harbours and the flow of marine traffic out to the Mediterranean and, via the Nile, into Egypt’s hinterland. Then, in the 4th century BC, something happened: perhaps the invading Persians, perhaps seismic activity, or perhaps the unsuitably soft sediment foundations faltered. Archaeological evidence certainly suggests that areas of the port were destroyed. And then along came Alexander the Great.

City in decline

In 331 BC, Alexander founded a city that took his name 30km (19 miles) to the west of Thonis, on more secure bedrock. Here he established a great harbour, Portus Magnus, and proceeded to transfer to Alexandria the administrative structures, economic power, and commercial trade links previously enjoyed by Thonis. By the 2nd century BC, even the name Thonis had become a distant memory, and the city was henceforth referred to as Heracleion.

For a while, the temple of Amun Gereb retained importance both as a symbol of the Ptolemaic kings and as a redistribution centre for what remained of the port until another natural disaster in the 2nd century BC destroyed at least part, if not all, of the building. The final death knell for Thonis-Heracleion came with the fall of the Ptolemaic dynasty, after which such symbols of dynasty were no longer relevant. What remained of the harbour trade dwindled while Alexandria continued to grow. By the time the Romans arrived at the end of the 1st century BC, the city was a shadow of its former self.

In AD 21 July 365, tidal waves devastated the coastline along the south-eastern fringes of the Mediterranean. Despite this, the city clung on: archaeologists have recovered artefacts dating to as late as the Byzantine period in the 8th century AD. But, following an earthquake in the second half of the 8th century, Thonis-Heracleion finally succumbed to the sea, and lay lost beneath the waves for the next 1,200 years.

ALL images: Christoph Gerigk ©Franck Goddio/Hilti Foundation, unless stated.

FURTHER INFORMATION
Maritime Archaeology and Ancient Trade in the Mediterranean, D Robinson & A Wilson (eds), Oxford Centre for Maritime Archaeology.
Egypt’s Sunken Treasures, Exhibition catalogue. Munich. F Goddio and D Fabre (eds.), published by Prestel, 2008.
Goddio, F, Topography and Excavation of Heracleion-Thonis and East Canopus (1996-2006). Underwater Archaeology in the Canopic Region in Egypt, Oxford Centre for Maritime Archaeology Monograph 1.

SOURCE: Franck Goddio, President of Institut Européen d'Archéologie Sous-Marine (IEASM), Director of Excavation at Thonis-Heracleion; David Fabre, IEASM. Visit: www.franckgoddio.org and www.ieasm.org.