The best way to see Switzerland by train is by purchasing a Swiss Travel Pass and following the "Grand Train Tour of Switzerland" route. This all-in-one pass is essential because it covers all public transport, including trains, buses, boats, and even some mountain excursions, while providing free entry to over 500 museums. A classic 10-day itinerary often starts in Lucerne, moves to the Jungfrau Region (Interlaken/Grindelwald) for alpine vistas, and then heads to Zermatt to see the Matterhorn. From there, you can take the world-famous Glacier Express—the "slowest express train in the world"—to St. Moritz, featuring panoramic windows that showcase the Alps in high definition. Another highlight is the Bernina Express, which crosses the spectacular Landwasser Viaduct. Using the SBB mobile app is highly recommended for real-time connections. Because the trains are famously punctual and interconnected, you can seamlessly transition from a lakeside city to a high-altitude glacier without ever needing a car, making it the world's most efficient and scenic rail experience.