In the February 22, 1996 Apostolic Constitution Universi Domini Gregis on the vacancy of the Apostolic See and the election of the supreme pontiff, John Paul II wrote: “By the time fixed for the beginning of the election of the supreme pontiff, all the cardinal electors must have been assigned and must have taken up suitable lodgings in the Domus Sanctae Marthae (St. Martha’s House), recently built in the Vatican City.” This marked a departure from a centuries-old tradition of accommodating the cardinals in the rooms close to the Sistine Chapel during the conclave. These ancient rooms in the Apostolic Palace and the Vatican Museums were very uncomfortable, with very few bathrooms and no air conditioning, which was a big drawback, considering the old age of the cardinals.
The new Domus Sanctae Marthae is located south of St. Peter’s Basilica in the area occupied by the old hospice of St. Martha. It is made up of two adjacent five-story buildings with a modern chapel, a large dining room, a library, a conference hall, 106 mini-suites, 22 single rooms, and a large state apartment.
The architecture of the two buildings is simple, the interior very functional, the rooms ample and furnished with good taste. The building is normally occupied by clergy working in the Curia and bishops passing through the Vatican: all of these must leave the building during the conclave. The only people admitted – doctors, confessors, masters of ceremonies, but also cooks and cleaning staff – are bound to secrecy about anything concerning the conclave.
The Constitution Universi Dominici Gregis states: “For the whole duration of the election the Cardinal electors are required to refrain from written correspondence and from all conversations, including those by telephone or radio with persons who have not been duly admitted to the buildings set aside for their use. Such conversations shall be permitted only for the most grave and urgent reasons, confirmed by the Particular Congregation of Cardinals.”
Since the Sistine Chapel, where the conclave is held, is located on the opposite side of St. Peter’s Basilica, the cardinals will have to be driven to and from the Sistine Chapel. The Constitution therefore prescribes that: “… provisions shall be made to ensure that no one approaches the Cardinal electors while they are being transported from the Domus Sanctae Marthae to the Apostolic Palace.”