Museo e Cripta dei Cappuccini

Roma Capitale describes the crypt as the Capuchins' former cemetery, realizzata verso la prima metà del XVIII secolo, five chapels decorated with the skulls and bones of about 4,000 friars, each chapel named for the bones used to decorate it, and each said by tradition to hold holy earth brought from Palestine or Jerusalem. Italian Wikipedia adds a separate fact that is easy to confuse with the first: the bones themselves were gathered between 1528 and 1870, from the order's old cemetery at Santa Croce e San Bonaventura dei Lucchesi. The making of the crypt and the gathering of the bones are two different dates and this guide keeps them apart. Italian Wikipedia quotes the plaque at the entrance: Quello che voi siete noi eravamo; quello che noi siamo voi sarete.