Hi Fred & Ziners,
We traveled to Rome and Florence in July 2001 and although
very crowded and hot it was enjoyable. My advice because of
the crowds is to plan and book your tours, museums, trains
etc. before leaving the USA. Getting up early to sightsee
and tour gives you a jump on the crowds. One example is by
arriving at the Vatican 8:30 AM, my family and I were the
only four people viewing the Pieta`. The same is true for
museums in Florence. If Paris is also on your itinerary buy
a Paris Museum Pass and again it negates the lines.
Hopefully this helps and enjoy your trip.
Vince, outside of Philadelphia