The best time to visit Walhalla is from June to October, when the weather is warm and pleasant, great for outdoor activities.June through August offers the warmest temperatures, with long daylight hours ideal for enjoying the lakes and forests. This is peak season, so booking accommodation and activities in advance is highly recommended, especially for families.For those who prefer slightly cooler weather and fewer crowds, September and October are excellent choices. The autumn foliage is stunning, particularly around the Manistee National Forest.