monastic living quarters, and the library. San Marco has been called the first Renaissance church, though it seems to be a compromise between the Trecento tradition and the Renaissance spirit. The plain white walls without frescos differ from the coloristic tradition of the Trecento and were essential to Michelozzo's architectural concepts and preference for large, unadorned surfaces, subtly articulated by necessary structural members in grey pietra serena. Like many of his projects, San Marco was constructed with incredible rapidity. Unlike Brunelleschi, Michelozzo was able to finish what he started, largely due to Michelozzo's efficiency and due to the availability of adequate financing from Cosimo throughout the campaign. The first part undertaken by Michelozzo was "the rebuilding of the old refectory, where a low vault, supported by consoles much like those in the sacristy at S. Trinita, was built to sustain the cells above. Work began on the church in 1438 and was probably completed three years later, though certainly by 1443 when it was consecrated by Pope Eugene. Using the perimeter of the former Trecento church, Michelozzo added a polygonal apse, similar in form to that at Bosco ai Frati; it was lighted by three long round arch pietra serena windows which can still be seen in the upper story of the convent. The pointed entrance arch rested on two pilasters with large, classical Corinthian capitals surmounted by a dado decorated with the Medici balls (also still visible). In front of the apse was the Capella Maggiore, covered with groin vaulting. The nave was a single open space without aisles, adorned with ediculas or altars (three on each side), and covered with a wooden beamed ceiling. Separating the nave and the Cappella Maggiore was a high wall (tramezzo) with two doors. In the later remodelling of the church, the wall was removed and the doors were transferred to the polygonal apse where they are now located. Their fluted pilasters are crowned with composite capitals identical to those in the Barbadori Chapel in S. Felicita by Brunelleschi, and above the architrave with classical mouldings, the frieze is decorated, like the capitals at Bosco ai Frati, with the Medici balls." Choir of the Santissima Annunziata Commissioned by Lodovico Gonzaga, lord of Mantua and general of the Florentine troops, the choir was created in commemoration of Gonzaga's father and "for the celebration of masses for his soul." Cosimo had already commissioned Michelozzo with