Beat the giant and followed Voss...

[Aixtreme]

All I want to know is: Will I be able to return to the vatican to discover the secrets that I did not solve up tp this point? I hope you understand what I'd like to know.
Thanks for your help!

[HeideKnight]

If I am not mistaken, at the end of each chapter one can travel to a previous location through the option "Travel" in the menu. It is definitely possible when having finished the main story. I am currently doing some side missions which I could not complete, yet, using this travel option.

[Omega X]

yes a travels tab will appear in the journal to go back to any location

[Aixtreme]

Thank you, guys!