The sacristy and chancel were added in 1877. The church has a single nave with a small sacristy. It comprises a nave, a main chapel, a sacristy, and a bell tower. It was adapted as part of the parochial sacristy of the new basilica. Beneath the frescoes, the psalters of the cathedral's sacristy are on display. The cathedral is typically Gothic, as is its sacristy, which is of great architectural value. There is an octagonal sacristy, surmounted by a dome. Subsequently, the ceremony moved inside the sacristy of the church. The space was originally a sacristy and choir room. Most of the noncombatants gathered in the church sacristy for safety. The sacristy is inside Frische Hall. Only the Gothic sacristy kept its slate roof. Lorenzo was locked safely in the sacristy by Angelo Poliziano. Medieval collections of the Lavra sacristy attracted thousands of visitors. The precious fragment is kept in the sacristy of Santa Maria in Cosmedin.