Are there any travel guides to Germany, France and Italy that you can recommend?

Last year, I went to these countries with Zhongxin's tour group. At that time, we mainly went to famous cities and scenic spots in these countries, including Interlaken and Lucerne in Switzerland. Rome, Florence and Venice in Italy; Paris, France; Cologne, Frankfurt and other places in Germany ~

Visas in these countries are common, but it is not enough to find the easiest country to handle. You must apply for a visa for the country with the longest stay according to your itinerary. If the stay time is the same, you need to apply for the visa of the first country to go ~