Jethou is a small island that is part of the Bailiwick of Guernsey in the Channel Islands. It is privately leased from the Crown, and not open to the public. Resembling the top of a wooded knoll, it is immediately south of Herm and covers approximately 44 acres (18 ha).

The Bailiwick of Guernsey is a self-governing British Crown Dependency off the coast of Normandy, France, comprising several of the Channel Islands. It has a total land area of 78 square kilometres (30 sq mi) and an estimated total population of 67,334.