Peristera Underwater Museum

The wreck off Peristera sank around 425 BC carrying roughly four thousand amphorae, probably wine from Mendi and Peparethos, and it is one of the largest ancient merchant ships known from the classical Aegean, big enough to overturn older assumptions about the scale of Greek shipping. The cargo lies where it fell, a field of stacked amphorae on the seabed between about twenty-two and thirty metres. In 2020 Greece opened it as the country's first underwater museum, allowing certified divers to visit with licensed guides, part of a wider policy shift after decades in which all ancient wrecks were closed. Non-divers can see the site through a virtual presentation at an information centre on Alonissos.

What you actually see

• The amphora field - thousands of stacked jars on the seabed.
• The hull outline - the shape of the cargo showing the vessel's size.
• The guided dive - visits with licensed operators in small groups.
• The surface centre - a virtual reality presentation for non-divers.

When to go

June to September, when dive boats run and visibility is best; the season is short and weather-dependent. Booking with an authorised centre in advance is necessary as numbers are capped.

Honest expectations

Access requires open-water certification and comfort at thirty metres, so it is not a beginner dive. Nothing may be touched or moved, and guides enforce that strictly. Boats are cancelled in wind, and the surface exhibit is a substitute rather than an equivalent.

Nearby

Patitiri and the Alonissos old village are on the main island; the marine park's Kyra Panagia lies north.