A large merchant ship that sunk around 425 BC near the island of Alonissos is the site of Greece’s first-ever underwater museum, touted by the regional governor as “the parthenon of shipwrecks.”

Located near the islet of Peristera off the island of Alonissos in the Sporades group and at a depth of 21-28 meters (around 90 feet), the underwater diving site will be open from 3 August to 3 October.

Non-diving tourists will be able to take a virtual reality tour at an information center in Alonissos.

The ship was carrying thousands of amphoras, ancient storage pots that were used to transport wine, olive oil and other food and beverage products between Greek city states.

For decades, this bonanza of history beneath the waves was off-limits to everyone except archaeologists. But in 2005, Greece revised a policy designed to protect the country’s undersea treasures from would-be looters, opening a select few sites to the scuba-diving public.

Greek Culture Ministry officials have said that four other underwater locations are set to open to divers, paving the way for Greece to become an important scuba destination.

A video shows the expansive area on the bottom of the sea that is Greece’s newest museum.