Guida
Lake Mashu is a caldera lake located within the Akan-Mashu National Park in Hokkaido. It is known as a mystical place, historically referred to in the Ainu language as 'Kamuy-to' (Lake of the Gods). The most striking feature is the deep blue water known as 'Mashu Blue.' The extremely high transparency of the water reflects the blue of the sky, captivating all who see it. Surrounded by steep cliffs, it is impossible to descend directly to the water's surface, but various observatories allow visitors to gaze down upon the magnificent landscape from high vantage points.
Formed by volcanic activity, Lake Mashu holds a deep history and is a place cherished by the Ainu people, with many mystical legends passed down through generations. The lake is also deeply connected to Japanese music culture; the 1966 song 'Kiri no Mashuko' (Lake Mashu in the Mist) made its name and the image of 'mist' famous across the nation. This song has made the ethereal, misty landscapes a symbol loved by many. Today, the area is strictly managed as a special protection zone within the National Park to preserve its pristine environment.
There are three primary spots to enjoy the scenery of Lake Mashu: the First Observatory, the Third Observatory, and the Ura-Mashu Observatory.
This is the most popular viewing spot and is accessible by large buses. The 'Mashu Lake Kamui Terrace,' renovated in 2022, is a modern facility featuring an outdoor rooftop terrace and an indoor lounge. From the well-maintained wooden decks, you can view the lake, the island of Kamui-shima, and the towering Mount Kamui-nupuri simultaneously.
This spot is less crowded than the First Observatory, offering a quieter environment to enjoy the view. However, access for large buses is restricted, so it is primarily visited by car, motorcycle, or bicycle.
Located near the border of Shari Town and Nakashibetsu Town, this observatory is at a relatively lower altitude. This characteristic often allows for a clearer view of the lake surface even when other observatories are covered in thick mist. Access is seasonal, typically available from April to November.
Lake Mashu presents a completely different face depending on the season and time of day. In summer, the 'Mashu Blue' shines brilliantly under clear skies, offering a calm and serene view. In winter (around February), you may see the surrounding mountains covered in white frost and the lake surface frozen over. During periods when mist is frequent, the landscape becomes incredibly mystical and otherworldly. To see the most vivid blue water, aim to visit on days with high clear-sky rates.
During the winter season, you can experience nature more closely through snowshoe trekking. Equipment rental is often available at facilities near the Kamui Terrace and surrounding areas. Walking through the snow while gazing at the lake and the surrounding landscape offers a unique charm different from standard sightseeing. There are also cafes and rest areas nearby where you can relax while enjoying the view.
Several other attractive sightseeing spots are scattered around Lake Mashu. For instance, at Mount Io (Atosanupuri), you can witness dynamic volcanic landscapes, the scent of sulfur, and rising steam. Near Lake Kussharo, you can enjoy lakeside strolls and activities like canoeing. Combining these areas allows you to create a perfect travel route to fully enjoy the nature of Eastern Hokkaido.
Because Lake Mashu is at a high altitude, temperatures can change drastically depending on the season. We recommend preparing appropriate clothing, especially warm gear for winter or bad weather. Please also follow local rules when using parking lots and observatories.