[1]: 105–128 Jersey experiences some of the largest tidal ranges in the world, up to 12 metres;[2] Guernsey has slightly less dramatic tides.

Modern navigation systems have helped reduce the number of disasters, but shipping still receive warnings of waters around the Channel Islands.

[5] Jersey Guernsey Alderney Other Open sea On 17 September, only two days after the sinking of the PSS Polka, Superb left St. Malo with sixty passengers and crew aboard, including Captain Priaulx and several of the other survivors from the Polka.

As they approached the Minquiers Reef, Superbs’ mate (John Fleming) was persuaded by some of the passengers to show them where the Polka had gone down but unfortunately, as he took Superb through the so-called eastern passage, she struck a rock known as La Pointue du Blanc Roc which tore deep into her hull.

In the ensuing panic to load the lifeboats, twenty people lost their lives, four of whom had barely recovered from their experiences on the sinking Polka two days previously.

Ironically, Superb herself remained stranded on the rock and the survivors including, once again, Captain Priaulx, were plucked straight off the decks by the rescue ships sent out from St. Helier.

One of the earliest steamships operating in the waters around the Channel Islands, the Superb was owned by the Jersey Steam Packet Company of St. Helier which ran her on their scheduled Jersey to St. Malo [and Granville] mail and passenger service.

[122][125] British Navy, cruiser built in 1940 accompanied by the destroyer Limbourne and five other vessels (Grenville, Rocket, Talybont, Stevenstone and Wensleydale) was engaged in an offensive sweep off the French coast between Ushant (Ouessant) and the Channel Islands on the night of 23 October 1943.

Visibility was poor and the vessels ran into the enemy light force of the German 4th TB Flotilla which managed to avoid their fire and to discharge a salvo of torpedoes with disastrous effect.