National Museum of Subaquatic Archaeology
MuseumThe treasure at the heart of this museum’s collection was once secretly flown to Florida under a code name, “Black Swan,” by an American company that spent years denying what it actually was. It took a Spanish government lawsuit, a five-year US federal court battle, and a final rejection by the Supreme Court to bring $500 million in gold and silver coins back to Spain — where it now sits on public display here in Cartagena.
The treasure that took five years and a Supreme Court to recover
In May 2007, Florida-based Odyssey Marine Exploration announced it had raised over 500,000 silver and gold coins from a shipwreck at 518 metres depth off the Portuguese coast, flying the haul back to Tampa under the codename “Black Swan” without disclosing its origin. Spain identified the wreck as the Nuestra Señora de las Mercedes — a Spanish naval frigate carrying royal treasure from Peru to Cádiz when British warships intercepted and sank it at the Battle of Cape Santa María in 1804, killing more than 200 people aboard in the resulting explosion. What followed was a genuinely landmark legal fight: a US federal court ruled in Spain’s favour in 2009, the appeals court upheld that ruling in 2011, and in February 2012 a US Supreme Court justice rejected Odyssey’s final emergency appeal, forcing the company to surrender roughly 17 tonnes of silver and gold. The recovered treasure now forms one of the centrepieces of ARQVA’s permanent collection.
Older wrecks, equally significant finds
The Mercedes treasure shares space with material spanning nearly three thousand years of Mediterranean seafaring. Among the oldest and most scientifically important are the remains of Mazarrón I and II, Phoenician trading vessels dating to the 7th century BC — one of them, Mazarrón II, was carefully extracted from the seabed in twenty separate sections as recently as 2025, after archaeologists determined the protective sand that had preserved it for 2,600 years was finally eroding away. A collection of elephant tusks bearing Phoenician inscriptions, unique anywhere in the world, sits alongside amphorae, lead ingots and a life-size reconstruction of a Roman merchant vessel.
Mazarrón I & II
7th-century BC trading vessels, among the oldest shipwrecks recovered anywhere in the western Mediterranean.
Inscribed elephant tusks
A collection of Phoenician-inscribed ivory, described as unmatched anywhere else in the world.
Two buildings, one underwater feel
Linked below ground level, the museum’s twin harbourfront buildings were deliberately designed to evoke the sensation of being submerged.
Free admission
As a state-run national museum, ARQVA offers free entry, a detail regularly praised by visitors given the scale of what’s on display.
Frequently asked questions
What is the “Black Swan” treasure?
The codename an American company gave to roughly 594,000 silver and gold coins it secretly recovered from a Spanish shipwreck in 2007, later proven in US courts to be the sunken frigate Nuestra Señora de las Mercedes and returned to Spain in 2012.
How did Spain win the treasure back?
Through a five-year legal battle in US federal courts, culminating in a Supreme Court justice rejecting the company’s final appeal in February 2012.
What are the Mazarrón shipwrecks?
Two Phoenician trading vessels from the 7th century BC, among the oldest ships ever recovered in the western Mediterranean, with Mazarrón II extracted from the seabed as recently as 2025.
Is entry free?
Yes — as a Spanish national museum, ARQVA offers free admission.
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How this page is maintained. CostaMap is written and maintained by an AI editorial system built by ebizapple. Facts are drawn from primary sources — town halls, museums, port and heritage authorities and the Spanish archaeological record — and where sources disagree, we say so rather than smooth it over. Photographs marked as ours are taken on location. This page was last reviewed on 10 August 2026. Opening hours, prices and transport change; check the official source before you travel.