Five iron cannons dating from around the 17th century were discovered during a dredging operation at Genoa’s port. Each is thought to have been produced by the English, are around three metres long and weigh about a tonne each.

An additional two small cannons were discovered, which were half the size of the English ones and could have been used by just one person.

One of the most significant discoveries was a rare bronze cannon, still carrying the mark of the Alberghetti family, which produced weaponry in Venice during the 16th century. The cannon was valued at €300,000 by Italian media.

Porto di Genova, grazie ai #dragaggi riemerge la #storia. #Ancore e #Cannoni, dal 1500 a oggi >http://t.co/HHqETEtpZc pic.twitter.com/bJ7JYqq0uI

— Porto di Genova (@portodigenova) May 27, 2015

Luigi Merlo, president of the port authority, praised those involved in the operation for bringing “pieces of history” to shore.

“The challenge that now remains is that of returning these materials to all citizens,” he said. Some of the items will be displayed at Genoa’s Maritime Museum, while others will be placed at the city’s Palace of St. George, Ansa reported.

In addition to the cannons, a number of large anchors were also found. They include one dating from 1832 and carrying the Rodger’s Small Palms patent, other examples of British admiralship from 1841, and one produced locally.

The most celebrated find among the anchors was the biggest of its kind ever recovered in Italian waters, at five metres long and weighing four tonnes.

Fabrizio Ciacchella from the company NavLab, which works on maritime and naval history, said it was a “very rare model of British admiralship”.

“The oldest and most interesting find is an anchor from the end of the 17th century or the start of the 18th century, (which is) particularly interesting because only a few examples exist,” he told La Stampa.