Bellagio is a town with steep, cobblestone walks. Some steps are so steep that you have a huge reach; so, when it rains, proper shoes will give you better footing.
It's a good idea to be fairly fit when going anywhere in Europe, but in Bellagio, you really need to be fit if you plan to enjoy the back streets.
You need to wear good walking shoes (never leather soles) that tie or velcro up.
The picture shows me on one such walk, and you can see what I mean.