An intercommunication system for a building or a delimited area with controlled access, characterised in that it comprises: - a first multimedia electronic device; - a support bearing a URL address made accessible from the outside close to an entrance to said building or delimited area, the URL address being detectable by means of the multimedia electronic device; - a series of operating instructions for displaying on said first multimedia electronic device a virtual map wherein a graphical element identifies, in said virtual map, a zone corresponding to said entrance and the association to it of said URL address; a remote server, connected to the Internet or to another geographical network suitable for data transmission and designed to receive a call with said URL address from the multimedia electronic device and to provide at least one web page, corresponding to said URL address, with associated telephone numbers of one or more addressees; - a database resident on said server and containing a series of said telephone numbers for displaying on said multimedia electronic device a list of said one or more addressees to which said building or delimited area refers in such a way as to allow one or more addressees to which said building or delimited area refer and set up a telephone call. - a first multimedia electronic device; - a support bearing a URL address made accessible from the outside close to an entrance to said building or delimited area, the URL address being detectable by means of the multimedia electronic device; - a series of operating instructions for displaying on said first multimedia electronic device a virtual map wherein a graphical element identifies, in said virtual map, a zone corresponding to said entrance and the association to it of said URL address; a remote server, connected to the Internet or to another geographical network suitable for data transmission and designed to receive a call with said URL address from the multimedia electronic device and to provide at least one web page, corresponding to said URL address, with associated telephone numbers of one or more addressees; - a database resident on said server and containing a series of said telephone numbers for displaying on said multimedia electronic device a list of said one or more addressees to which said building or delimited area refers in such a way as to allow one or more addressees to which said building or delimited area refer and set up a telephone call. - a support bearing a URL address made accessible from the outside close to an entrance to said building or delimited area, the URL address being detectable by means of the multimedia electronic device; - a series of operating instructions for displaying on said first multimedia electronic device a virtual map wherein a graphical element identifies, in said virtual map, a zone corresponding to said entrance and the association to it of said URL address; a remote server, connected to the Internet or to another geographical network suitable for data transmission and designed to receive a call with said URL address from the multimedia electronic device and to provide at least one web page, corresponding to said URL address, with associated telephone numbers of one or more addressees; - a database resident on said server and containing a series of said telephone numbers for displaying on said multimedia electronic device a list of said one or more addressees to which said building or delimited area refers in such a way as to allow one or more addressees to which said building or delimited area refer and set up a telephone call.