They are not far away. The Isles of Scilly lie just 20 nautical miles south-west of Land's End, the south-west tip of Cornwall. And yet the archipelago, consisting mainly of around 140 stones and rocks as well as five larger, inhabited islands, has it all.
Strong winds from the west usually prevent you from setting course for the islands. And if you do manage to do so thanks to persistently calm weather conditions, there is virtually no sheltered anchorage on site - let alone a harbour. The passages between the islands are also peppered with shallows. They were once the English fleet's undoing.