Onami Pond, or Onami-ike, is the highest crater lake in Japan, situated within the Kirishima volcanic mountain range. It's a significant natural landmark, offering a unique opportunity to experience Japan's volcanic landscapes and pristine nature. The hike to the pond's rim provides panoramic views of the lake itself, surrounding volcanoes, and unusual rock formations, making it a popular destination for nature enthusiasts and hikers.
Visitors frequently highlight the stunning beauty of the lake, particularly its vibrant color on clear days, describing it as a "fairy lake" and "breathtaking." The effort required for the uphill climb is consistently deemed worthwhile for the spectacular vistas. Many reviewers recommend packing food and drinks to enjoy at the top, emphasizing the rewarding experience of resting by the lake. While the main trail to the pond is generally considered manageable for various fitness levels, some sections, especially the final ascent, can be challenging, with numerous stone steps. Reviewers note that even children and older individuals have successfully completed the hike, though it requires a certain level of stamina.
For a comfortable visit, wear sturdy walking shoes or hiking boots, as the trail involves many stone steps and can be uneven. Bring plenty of water, especially during warmer months, and snacks or a packed lunch to enjoy at the summit. Sunscreen and a hat are advisable, as parts of the trail are exposed, and it can be windy at the top. The best time to visit is on a clear day to fully appreciate the lake's color and the surrounding views. Allow at least 2-3 hours for the round trip to the pond and some time at the top; if you plan to hike around the entire lake or combine it with other peaks like Mt. Karakuni, allocate 4-5 hours or more. There are no toilets directly at the pond, so use facilities at the trailhead if available.
Access to Onami Pond is primarily by car or bus. If driving, there are a few small parking lots near the trailhead, some with toilets, but they can fill up quickly, especially on weekends. Reviewers suggest arriving early. Alternatively, some visitors mention parking along the roadside near the entrance. For public transport, one reviewer detailed a bus route from a hostel near Kirishima Jingu Shrine, involving a transfer in Marano Falls. This suggests that while possible, bus access might require careful planning and understanding of local schedules. The trailhead itself is clearly marked.
A common complaint is underestimating the difficulty and duration of the hike. Many visitors expect a leisurely stroll but find themselves facing a significant uphill climb, often taking 40 minutes to over an hour to reach the pond. To mitigate this, prepare for a moderate hike with sustained uphill sections and numerous steps. Don't be fooled by maps that might make it seem closer; it's a proper trek. Also, some visitors were unaware of the lack of facilities at the pond itself, so plan accordingly regarding restrooms and refreshments.