San Marco
- Type of ship: Armed freighter
- Lenght: 118 meters
- Position: 1 mile south of the Islandof Serpentara
- Depth: 96 to 107 meters
The Ex War Summit, was build 1919 in Newcastlebelong to the Societa’ An. Coop. di Navigazione Garibaldi in Genova.
The 1st of June 1941, on the way from Civitavecchiato Cagliari, at 8.50am, one and a half mile south of Serpentara,the ship was attacked by the british submarine HMS Clyde,and sank after two minutes.