Saint Lucia is 3.4 times larger than Aruba.
Area: 180 km2 World Factbook
Population: 110,663 (July 2014) World Factbook
Aruba is an island 33 kilometres long; it is located about 1,600 kilometres west of the Lesser Antilles in the southern Caribbean Sea and 27 kilometres north of the coast of Venezuela. Together with Bonaire and Curaçao, it forms a group referred to as the ABC islands. Wikipedia
Area: 616 km2 World Factbook
Population: 163,362 (July 2014) World Factbook
Saint Lucia is a sovereign island country in the eastern Caribbean Sea on the boundary with the Atlantic Ocean. Part of the Lesser Antilles, it is located north/northeast of the island of Saint Vincent, northwest of Barbados and south of Martinique. Wikipedia