Cardinal Carlo de' Medici provided Maruscelli with his most significant commission, the rebuilding of the Palazzo Madama, Rome, between 1637 and 1642. Originally built in the late 15th century for Sinulfo di Castel Ottieri and acquired in 1505 by the Medici, the palace had been the family seat in Rome during the pontificate of Leo X. Various proposals, including schemes by Giuliano da Sangallo and Lodovico Cigoli, had been made for reconstructing the palace before Maruscelli began work in 1637. The majestic façade (1638-1639) is a heavily decorated version of the standard Roman palace type. A new street, the Corsia Agonale, opened a vista to the palace door, and gave the Medici their long-sought link with the Piazza Navona. Cosimo III de' Medici later established the Accademia Fiorentina (1673-1686) in the Palazzo. Gaetano Koch performed restoration work ca. 1904. It is currently the home of the Senate of the Italian Republic (since 1871).