When we read about this corridor it was clear that we wanted to visit it (also because there are not many tours around).
We had the luck to have Mario Gesù as a guide (he does also other tours, see FlorenceTown). He does the tour in a very good way, including the guests and not only talking.. So first about 90 minutes in the Uffizi (we were lucky in that in December 2012 there were not too many people around. You could see Leonardo, Botticelli etc. without hassles) and then at least another hour in the Corridor from the Uffizi all the way to Palazzo Pitti crossing the Arno on the 2nd floor of the Ponte Vecchio... You wouldn't guess from outside that it's full with art. In the corridor you will see the world's most important self-portrait collection (Tintoretto, Corot, Rembrandt etc. etc.).
So if you're ready to spend 3 hours and like arts: do it. If you just want to have a look at the corridor you'll propably get bored after some time.
Would definitely do it again.
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