Rome is witnessing unprecedented security controls for the Pope's funeral, including restrictions on air travel over the city to avert the possibility of a terrorist attack, according to the offical tourism authority.
The Italian State Tourist Board said security is already "at maximum levels".
"Air space over Rome will be off limits and there will be controls both on the land and in the air," the body said in a statement.
"An unprecedented event, which requires maximum security to cover every possible risk plus that of a terrorist attack."
Extra trains will be put on to help cope with the influx of more than two million people, including Irish pilgrims, expected to arrive in the Italian capital this week.
Some stations will remain open for 24 hours and the transport authorities have guaranteed there will be no strikes on public transport until April 15 th, according to the tourist board.
The body said it was "highly advised" that people do not take private cars into the city centre.
Those in search of accommodation or parking facilities should visit the website www.comune.roma.it or call the Comune di Roma on 0039 060606.
Fiumicino and Ciampino airports are preparing to receive what the tourist board called "this enormous influx" of people. Some 15 extra medical points have been set up with over 200 ambulances and 600 doctors and nurses to man them.
The Italian Government has declared three days of national mourning but schools and public offices will remain open during this time. Shops, banks and other services will run normally, but some may shut during the funeral service on Friday.
There will be one minute's silence at midday on Friday during the funeral.