The secrets of a mysterious Nile party boat: what exactly lies hidden in the harbour of Alexandria?

Beneath the waters of Alexandria’s eastern harbour, an extraordinary shipwreck has been discovered: a thalamagos, often referred to as a Nile party boat. This new archaeological find paints a more nuanced picture of this iconic type of vessel and prompts scholars to rethink not only the economic, religious and social life of ancient Alexandria, but also how people of the time sought entertainment.

Along Alexandria’s Mediterranean coastline, in what is now the city’s eastern harbour, splendid structures once stood—harbours, palaces and temples—which later sank into the sea. As a result of earthquakes and rising sea levels, these remains disappeared for centuries, until the European Institute for Underwater Archaeology, in cooperation with Egypt’s Ministry of Tourism and Antiquities, began to bring them back to light—at least in a scientific sense.

One of the central sites of this research is Antirhodos Island, where archaeologists uncovered the temple of the goddess Isis, renovated by Cleopatra VII, as well as the Timonium, the palace of Mark Antony. Numerous shipwrecks have also been found in the surrounding area, collectively telling the story of how Alexandria evolved from the centre of the Ptolemaic dynasty into one of the Roman world’s most important economic engines—though there has been no shortage of unexpected discoveries either.

The discovery of the Nile party boat

According to The Conversation, during high-resolution sonar mapping of the former Royal Harbour, alongside a smaller vessel and a 30-metre-long merchant ship, researchers identified a peculiar wreck that was initially thought to have served a commercial, cargo-transport function as well.

However, throughout 2025, each dive revealed new details that gradually called this assumption into question. The wreck measures around 28 metres in length and 7 metres in width, with a flat bottom and a broad, box-like hull. Its asymmetrical bow and stern were gracefully curved, lending the original vessel an elegant appearance. At the same time, it lacked a mast step, suggesting that it was not a sailing ship but rather propelled by oars.

Greek decorative motifs carved into the planking indicate that it was built and repaired in Alexandria. Even so, its overall form did not correspond to the parameters of a seagoing cargo ship, deepening the mystery—until researchers turned their attention to ancient written sources.

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The thalamagos served multiple functions

Among Ptolemaic and Roman-era papyri, around 200 texts have survived that name various types of river vessels. Among these, albeit rarely, the thalamagos—literally a cabin ship—also appears, which is why the recent find is often described as a Nile party boat. An iconographic parallel can be seen in the Palestrina mosaic, where a crescent-shaped, oared vessel bears a striking resemblance to the Alexandrian wreck.

In Roman literature, the thalamagos had a notorious reputation. Seneca called it “a toy of kings”, while Strabo reported that Alexandrians held banquets and festivities on these vessels, especially during celebrations in nearby Canopus. These accounts, however, are heavily biased, as Roman authors often sought to emphasise the luxury and moral decadence of the Ptolemaic court.

Administrative documents, by contrast, present a far more nuanced picture. The Nile party boat was not merely a luxury yacht of its age: it was also suitable for transporting goods and was used for riverine travel.

When and how did people party in Alexandria?

The location of the wreck opens up further interpretative possibilities. The vessel was found close to the temple of Isis, and it is conceivable that it was destroyed in the same earthquake that caused the sanctuary’s collapse. It is possible that the Nile party boat functioned as a temple barge used during festivals dedicated to Isis.

This festival, marking the arrival of spring, symbolised the opening of the sea and was intended to ensure the safety of the grain fleets supplying Rome—although in Strabo’s accounts it appears more as a scandalous revel.

Detailed post-excavation analyses are still under way, as researchers aim to reconstruct precisely what the Nile party boat looked like. One thing is certain: this sunken thalamagos is not merely a simple wreck, but a key that may unlock a deeper understanding of the world of ancient Alexandria.

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