After looking at the reviews we picked up our tickets from the referenced bookstore (10 busy street mins away) the day before. On the day we got there early to take some photos and managed to be one of the first few in (Queueing slighty left of the middle out front before the signs etc went up). Inside the Pantheon to the left is where you get your audio guide and headphones, again this was unclear in the description as I was worried you also had to pick it up at the bookstore but no, inside the Pantheon - handed over some ID before following the audio tour around. The audio guide, as well as the incredible Pantheon, was a great start to the days exploring!

Incredible. Definitely worth the extra for this tour of the underground if you can afford it. My 9yo son was entranced, as were we. The guide did a great job of setting the scene and of explaining the context and relevant political climate. We were given headsets and radios to hear our guide at all times which was great. Byo headphones to save on rubbish or keep for the next tour as Rome must discard thousands of sets every day.

It was a good experience, fantastic building and audio guide is good, however the whole concept of having to walk hundreds of meters away from the site, to collect a pre-printed piece of paper with no time slot or ID, to then walk back just to get inside is rather ridiculous. And the time-slot doesn’t mean anything. Just turn up when you want.