My wife and I visited Verona in early September 2017. We had a fantastic day here, walking around and exploring in the late summer sunshine.
The UNESCO entry for this location specifically mentions the legacy of the Roman era, the medieval era, and the Venetian era, and I actually found it really easy to wander around and spot parts of each on display. It's such a great city for exploring and discovering, with cool little history tidbits along the way.