While it is technically possible to visit Rome, Venice, Milan, and Zurich in 8 days, it would be a packed itinerary with limited time to fully explore each destination. Here are a few things to consider:

1. Distance and Travel Time: Rome, Venice, Milan, and Zurich are located in different regions and countries, which means you would need to allocate travel time between each city. Traveling by train or air would be the most convenient options, but keep in mind that transportation and transit times can eat up a significant portion of your limited 8-day timeframe.
2. Sightseeing and Exploration: Each of these cities has a wealth of attractions, historical sites, museums, and cultural experiences to offer. Trying to cover all the major highlights in each city within a short time frame can be challenging. You may have to prioritize and choose a few key attractions in each city to visit.
3. Fatigue and Rushing: Moving between cities every few days can be tiring and may leave you with limited time to relax and truly immerse yourself in the local atmosphere. It’s important to factor in rest and downtime during your trip to avoid feeling overwhelmed or exhausted.
4. Local Experiences: One of the joys of travel is experiencing the local culture, cuisine, and ambiance of a place. With a tight schedule, you may have limited opportunities to explore local neighborhoods, try local delicacies, and engage in authentic experiences that go beyond the typical tourist attractions.

Considering these factors, it’s advisable to prioritize and focus on a smaller number of destinations to make the most of your 8-day trip. For example, you could choose to explore Rome and Venice in Italy or combine Milan and Zurich in Switzerland. This would allow you to have a more relaxed and fulfilling experience in each location, with sufficient time for sightseeing, exploration, and immersing yourself in the local culture.

Alternatively, if you prefer a faster-paced trip and are content with brief visits to each city to get a taste of their highlights, you can consider the broader itinerary. Just be prepared for long travel days and limited time in each location. It’s essential to plan your itinerary carefully, consider the logistics of transportation, and be realistic about the time constraints to ensure an enjoyable trip.