going to italy

The Roma Pass is sold at the covered attractions as well as at Tabacco shops throughout the city. REad the details there about how it works. Only the first two or three sites that you visit are fully covered and others just discounted. If you want to use it to cover entrance to the Borghese Gallery then you must make that reservation by phone. It does not cover the Vatican Museums, which you can reserve separately to avoid the ticket purchase line. Visits to St. Peter's Basilica are free.

You can buy it at the airport also - here is something I copied from Tripadvisor:

"I have seen this question many times. Here is where you buy the Pass. Head straight out of baggage claim. You will see an airport information desk. Do not exit. Turn right. On the left side, you will see store fronts (you are still in the airport) the second shop is a tobacco shop, the third is the Tourist INformation Center."

Note: did buy mine at the first venue that I needed to use it - not at the airport. They are a good bargain if you are going to a few sites.

Also something not frequently mentioned. Go to the top of the The Wedding Cake.
Il Vittoriano. The Victor Emmanuel Monument - it is across the streets from the Forum and Colosseum - take the elevator to the top and there is a 360 view of all of Rome. We spent over 30 minutes up there taking photos - and admiring the views. It was great to see where things are located around the city