A depot is an area where the totality of documents handed over to the Archives, is kept and is the treasury of the written documents for the history of Belgrade. The depot of the Historical Archives of Belgrade has an area of 2,400 sq meters and is separate from the Archives premises. It is provided with an electronic lock with the cards enabling access to the depot to authorized persons only. The door is made of metal and the total area is covered with fire sensors and instruments measuring the temperature and air humidity. An air conditioning system has been installed and the windows have roll down Venetian shutters. This way the conditions have been created for the protection from the greatest enemies of the documents – fire, water and sun's rays. The documents are filed in cardboard boxes and folders made in the Archives itself, placed following a previously determined location on metal shelves accepting 20,000 shelf meters of documents.