I have been many times to Italy, and my usual set of lenses is 35mm & 50mm. I never feel like I need a wider lens. Things will look distorted with lenses wider than 28mm. Things will also look smaller and unreal for my perspective in street photography. The 50mm lens is a must for me. It can be used as a "normal" lens and as a short tele [just get closer to the subject]. In Venice, I went up the church tower to take photos of the San Marco plaza with the many people and pigeons. My iPhone has a wide angle lens. This will do. The 50mm lens is often a Sonnar 50/1.5 and the 35mm is usually the pre-asph Summilux 35/1.4. The iPhone is best for close-ups in street photography from the hip.
I never use a tele in such trips. It will be an extra load to carry and then you don't use it. Make the 50mm lens your fast tele.
Don't forget to enjoy your trip. Eat Gelato!