September is the most popular time to visit Altstadt Frankfurt, as the city comes alive with vibrant energy and cultural events. During this month, the pleasant autumn weather beckons travellers to explore the historic streets, where you can admire stunning architecture and enjoy outdoor cafés. The peak season extends from September to November, making it an ideal period for those who appreciate a bustling atmosphere filled with festivities.As temperatures in September typically range from 10 to 20 degrees Celsius, visitors can comfortably stroll through the picturesque alleys, visit the iconic Römer, and take in the sights along the River Main. This time also coincides with the Frankfurt Book Fair, attracting literature enthusiasts from around the world and offering a unique cultural experience.For those seeking a more budget-friendly option, consider visiting in March. During this time, this month presents the opportunity to enjoy the charm of Altstadt Frankfurt without the crowds. You can explore the local museums and galleries at a more leisurely pace, soaking up the city's rich history and culture.Ultimately, your choice of when to visit Altstadt Frankfurt will depend on whether you prefer the lively option of the autumn months or the tranquil charm of early spring.