The best time to go to Kastel Stafilic is during the shoulder seasons of May, June, September, and early October. These months offer pleasant weather, fewer crowds, and a more relaxed experience compared to the peak summer months.Couples looking for a romantic getaway will appreciate the warm, sunny days and comfortable evenings during May and June. You can enjoy strolls along the promenade, dine at waterfront restaurants, and explore the historic kastels without the intense heat or large crowds of mid-summer. The sea is also warm enough for swimming by late May.For travelers seeking a relaxed beach vacation, September and early October are ideal. The sea remains warm from the summer, making it great for swimming and water activities. The temperatures are mild, and the atmosphere is generally more tranquil, allowing for a peaceful stay.