I really like this article since it sums up the basics of the places most people want to see and can be a great precursor to further research.  Certainly makes me want to visit! 

https://www.travelwithoutlimits.com.au/accessibility-in-the-eternal-city/

travelwithoutlimits.com.au

Accessibility In The Eternal City | Travel Without Limits

Travelling to Rome as a wheelchair user cemented this belief for me: although travelling as a wheelchair user isn't always easy, it's always worth the effort.