The "Casa del Almirante" is a palatial house, adjacent to the Plaza San Martín in the Barrio del Pópulo, which was constructed in 1690 with the proceeds of the lucrative trade with the Americas. It was built by the family of the admiral of the Spanish treasure fleet, the so-called Fleet of the Indies, Don Diego de Barrios. The exterior is sheathed in exquisite red and white Genoan marble, prepared in the workshops of Andreoli, and mounted by the master, García Narváez. The colonnaded portico, the grand staircase under the cupola, and the hall on the main floor are architectural features of great nobility and beauty. The shield of the Barrios family appears on the second-floor balcony.