The bunker is hidden in the very heart of Villa Ada Savoia, between the thick woodlands and it'll be impossible to reach it by yourself.

Therefore the guided tours will start either from:

Via Panama 55 / Largo Bangladesh, at the Bar "Panamino"

or from

Via Salaria 267

This depends on the kind of tour you choosed.

The walk inside the park to the bunker takes 10 minutes from Via Panama, while from via Salaria it takes 15 minutes. The guided tour will start already during the walk: the guide will tell you about the Villa and will give general historical  informations before getting to the shelter.