Finding the office is not so simple. Termini is a gigantic mall, very airport-like, with a zillion corridors, escalators and departure gates. The left luggage office is tucked way back in the innards of the building and involves quite a bit of walking (and asking for directions). I would use this option only if there were no other solution, as it seemed quite a hassle to me - unless you are traveling by train, of course, and stopping at Termini in any case.


