The name change to La Unión Historical milestone · La Unión, Campo de Cartagena, Murcia Image of La Unión, not of the place itself. The disagreements between the residents of El Garbanzal and those of Herrerías were settled in 1868 with a merger promoted by general Prim, out of which came the name of La Unión for the young mining municipality. 1868 Photo: Nanosanchez (Public domain) What to see and do in La Unión