Agua is part of a group of four volcanoes that surround the city of Antigua, Guatemala. The others include Pacaya, Acatenango, and Fuego. Pacaya and Fuego are still very active.
Parents refers to a larger category under which an object falls. For example, theAconcagua mountain page has the 'Aconcagua Group' and the 'Seven Summits' asparents and is a parent itself to many routes, photos, and Trip Reports.