Martinique
The most southerly island of the Windward Islands in the Caribbean Sea is Trinidad. There are 14 islands in this group and most were formed from volcanic activity. Barbados is essentially a huge mass of coral.
the most northely island group in the UK is the cook island people
There is more than one archipelago known as the Windward Islands. The most well-known is in the south of the Caribbean. The largest island in these Windward Islands is Dominica, with an area of 750 km2 or 290 sq mi. There is also a Windward Islands in the eastern part of the Society Islands, French Polynesia. The largest island here is Tahiti, with an area of 1045 km2 or 404 sq mi. There is another Windward Islands that is used to refer to the southeastern part of the Hawaiian Islands. The largest island in Hawaii is also the most southerly and the most easterly island in the state. This is Hawaii itself, or the Big Island, with an area of 10 433 km2 or 4028 sq mi.
The Island of Unst is the most northerly island on Britain.
Ellesmere Island
That's the Shetland Islands.
Hokkaido
Boigu Island is the most northerly inhabited island in Australian territory. It is part of the top-western group of the Torres Strait Islands. Cape York, on Cape York Peninsula, Queensland, is the northernmost tip of the Australian mainland.
The most northerly part of the Irish province of Ulster is Malin Head in county Donegal. It is also the most northerly point on the island of Ireland.
cayman island
Out Stack... or Muckle Flugga
Lesser Antilles