Welsby is the central part of Bribie Island. The
Pumicestone Channel (also known as Pumicestone Passage) is its western coastal border and the
Coral Sea is its eastern coastal border. Almost all of Welsby is within the
Bribie Island National Park or the Bribie Island State Forest. Apart from these protected areas, the remaining land is a very narrow strip along the west coast beside the Pumicestone Channel. Welsby has the following points: • Gallagher Point () • Mission Point () • Offshore are the following marine passages: Welsby has the following passages: • Gallagher Gutter () close to the western shore extending into
White Patch to the south • Pumicestone Channel () further offshore on the western side extending from
Moreton Bay at
Bongaree on the south-westernmost part of Bribie Island through Welsby to the very northernmost tip of Bribie Island (
Bribie Island North) where it connects to the
Coral Sea at
Caloundra There are two lagoons on the eastern shore of the locality: • Mermaid Lagoon () • Welsby Lagoon () == History ==