In the Bay of Gibraltar (also known as Algeciras Bay) 151 new underwater archaeological sites have been identified, with 34 wrecks documented in detail covering a chronological period from the 5th century BC to the 20th century AD. The discovery – result of the Herakles Project conducted by researchers from the University of Cadiz between May 2020 and March 2023 – also made it possible to identify the wrecks of Roman, medieval and modern ships.
Until 2019, the Bay of Gibraltar was almost unexplored from an archaeological point of view: of the 125 archaeological sites surveyed in the area, only four were located underwater. And of these, only one was a wreck: the wreck of the Dancera 17th century vessel with Italian ceramics on board. The rest of the seabed of the bay, one of the busiest seaports on the planet since ancient times, was unknown from an archaeological point of view. No one had studied it systematically since the mid-1980s.
The most significant element from a methodological point of view is that the vast majority of the finds were located less than ten meters deep, with some directly reachable from the shore. In the first diving campaign, in just three weeks, 17 new sites were identified. In the following months, operating without the need for a support vessel and at depths between four and eight metres, the team located over 80 exposed sites on the seabed.
The abundance of remains required a selective strategy: documenting as much as possible in the minimum time and with the minimum impact. At the end of the field work phase, the overall balance was 151 sites: 124 classified as wrecks, 7 anchoring points and 20 isolated objects, such as anchors, ceramic fragments, elements of nautical equipment. Of all these, 34 wrecks have been documented with detailed techniques: underwater photogrammetry, 360° video, three-dimensional models and digital floor plans. Only in one of the 151 sites was it deemed necessary to carry out an excavation, opting for a generally least invasive strategy possible.
The catalog of wrecks found in Algeciras Bay covers almost the entire history of navigation in the Strait of Gibraltar. The oldest was named Timoncillo I, dated to the 5th century BC, in the Punic era. Alongside it, six other sites from the same period confirm that the bay was an active naval transit space long before the arrival of Roman rule. This is followed by Roman, medieval, Renaissance, modern and contemporary vessels, including British, Spanish, Venetian and Dutch vessels.
Among the most interesting finds is the Puente Mayorga IV gunboat, a small Spanish warship from the late 18th century. It is a type of light vessel, designed for rapid maneuvers: it approached enemy ships disguised as a fishing boat, then revealed its identity by opening fire with cannons mounted on the bow. Inside the wreck, a wooden box in the shape of a book was found, initially interpreted as a possible container for confidential documents. Close examination made it clear that it contained two wooden combs.
The researchers also reported concrete risks to heritage conservation. In fact, almost half of the sites surveyed require urgent protection. The anchors of the large container ships that frequent the port are dragged along the seabed during manoeuvres, with potentially destructive effects on remains found in the bay. Added to this is the spread of invasive algae Rugulopteryx okamuraewhich is covering the seabed and accelerating the degradation of materials. Fortunately, a new project aimed exclusively at the conservation of underwater heritage has recently been presented.
