For a pleasant visit to Glenarm, the best time to go is during the late spring, summer, and early autumn months, specifically from May through September.During these months, you'll experience the mildest weather, with average temperatures ranging from 10°C to 18°C (50°F to 64°F). This period offers the most daylight hours, allowing for extended exploration of the Glenarm Castle and its Walled Garden, as well as scenic drives along the Antrim Coast Road. It's also when local events and outdoor activities are most prevalent.For travelers who prefer fewer crowds and slightly cooler temperatures, May, June, and September are ideal. The gardens are often in full bloom or showcasing their autumn colors, providing beautiful backdrops for photography and leisurely strolls.