Interlaken is situated in the heart of Switzerland between Lake Thun and Lake Brienz. Known for its panoramic views of the Swiss Alps and an array of outdoor activities, it is a perfect spot to start your trip. The city center is perfect for a leisurely stroll, and there's an opportunity to experience Swiss cuisine by eating in one of its many restaurants.
Your second day on the itinerary will be spent at Mount Jungfrau. This UNESCO-protected Swiss Alps region is famous for the "Top of Europe," the highest railway station in Europe situated at an altitude of 3,471m (11,388 ft). Explore the Ice Palace with its fascinating displays and enjoy the panoramic views from the Sphinx Observation Terrace and Aletsch Glacier.
The third day is dedicated to Mount Titlis, a mountain in central Switzerland that is famous for the Titlis Cliff Walk, the world's highest suspension bridge offering stunning views of the Swiss Alps. At the top, there's also the Glacier Park, which is one of the world's highest situated playgrounds.
If you have an extra day, consider visiting the nearby picturesque alpine village of Lauterbrunnen with the Trümmelbach Falls - a series of ten glacier-fed waterfalls hidden inside the mountain. Or if you have less than four days, consider dropping Mount Titlis and take a quieter day exploring the Lakes Thun and Brienz and the picturesque towns of their respective namesakes.