Juan Díaz de Solís arrived again to the renamed Río de la Plata, literally river of the silver, after the Incan conquest. He sought a way to transport the Potosi's silver to Europe. For a long time due to the Incan silver mines, Potosí was the most important site in Colonial Spanish America, located in the current department of Potosí in Bolivia and it was the location of the Spanish colonial mint. The first settlement in the way was the fort of Sancti Spiritu, established in 1527 next to the Paraná River. Buenos Aires was established in 1536, establishing the Governorate of the Río de la Plata.