Which archipelago includes the islands of Guernsey, Jersey, Alderney, and Sark?

The archipelago that includes Guernsey, Jersey, Alderney, and Sark is the Channel Islands.

The islands lie in the English Channel just off the coast of Normandy. They are organized into two separate Crown Dependencies: the Bailiwick of Jersey and the Bailiwick of Guernsey. Although the United Kingdom handles their defence and international relations, the islands are not part of the UK and have their own governments, laws, and tax systems.

A common mix-up is treating the Channel Islands as a single political unit. “Channel Islands” is primarily a geographical name, while Jersey and Guernsey are administered separately. The archipelago also includes Herm, Jethou, Brecqhou, and numerous smaller islets. It should not be confused with the Scilly Isles, which lie off southwestern England, or with the French Chausey Islands, which are nearby but belong to France.