The best time to visit Kalisz is during the late spring and summer months, specifically from May to September, when the weather is at its most pleasant.During these months, you'll experience warmer temperatures and more sunshine, which is ideal for exploring the city's outdoor attractions. The average daily temperatures range from 15°C to 25°C, making it comfortable for walking around the Old Town and enjoying the parks along the Prosna River.This period is also when Kalisz hosts various outdoor events and festivals, offering a livelier experience. For instance, the annual Kalisz International Theatre Meetings often take place in late spring, and there are numerous open-air concerts and cultural happenings throughout the summer.For those who prefer slightly cooler weather and fewer crowds, May and September are particularly good choices.