A bank may not intuitively seem like an interesting place to visit on your tour of Madrid, but hold the phone. Founded in 1782 by King Carlos III, the Banco de España is perhaps one of the most beautiful banks in the world. Being the national central bank of Spain, it is bestowed with the function of supervising the Spanish banking system alongside the European Central Bank. However, judging by the building, you would not suspect this. Not only is the building a sight to behold, but the interior is adorned with artwork from the 15th Century onwards. While there are several portraits of Spanish royalty and notable people, one of the most prized portraits is probably that of the founder King Carlos III, painted by none other than the famous artist Francisco de Goya. Truly, a place that is both functional and aesthetically amazing.