Okama Crater: Zao's Emerald Eye

Okama Crater, nestled atop Mount Zao, is a breathtaking testament to nature's artistry. Formed in the 1720s by a volcanic eruption, this caldera lake is renowned for its mesmerizing colors, earning it the nickname 'Goshiki-numa' or 'Five Color Pond'. The water's hue shifts dramatically with the seasons, weather, and even the angle of sunlight, creating a captivating spectacle that ranges from turquoise to emerald green. Located at an altitude of approximately 1,600 meters, Okama boasts a circumference of roughly 1,080 meters and a depth of 27 meters. The lake is surrounded by the peaks of Mount Katta, Mount Goshiki, and Mount Kumano, adding to its dramatic setting. The water's high acidity prevents any aquatic life, contributing to its otherworldly appearance. Visitors can reach Okama via the Zao Echo Line, a scenic mountain road that offers stunning views. While the crater is inaccessible during winter due to heavy snowfall (typically from early November to late April), the journey to witness this natural wonder is well worth it during the warmer months. Be sure to check weather conditions before visiting, as the crater may be obscured by clouds.