 Asunción is one of the oldest cities in South America and the longest continually inhabited area in the Río de la Plata Basin; for this reason it is known as "the Mother of Cities".From Asunción the colonial expeditions departed to found other cities, including the second foundation of Buenos Aires and other important cities such as Villarrica, Corrientes, Santa Fe and Santa Cruz de la Sierra.Asunción is considered a 'Gamma City' by the Globalization and World Cities Research Network.