We would like to go from Rome through these two countries then on to Germany and back to France. Any advice or warnings?
The Gotthard Tunnel is the longest tunnel in the world and is the only one you should watch out for. They only allow a certain number of cars through at a time and there can be long waits. I would add on a couple of hours to your journey at that part if you are driving from Switzerland to Italy, apart from that. No dramas! almost 10 years ago
If you plan to drive over a mountain pass or two, make sure it is open. Some can be closed surprisingly deep into spring or summer due to unseasonal snow. Going over the passes makes for far more spectacular views, though it is much slower than the tunnels. Depends if you are just trying to get from A to B or see some places on the way. almost 10 years ago
I would recommend going through Bozen-Bolzano in the North of Italy into Austria and then go West toward Switzerland (via Bodensee - Lake Constance).
This way is pretty spectacular and you can stop off in a lot of locations on the way. almost 10 years ago