Toyoni Lake

Lake Toyoni is a freshwater lake located in Erimo Town in southeastern Hokkaido, sitting at approximately 260 meters elevation within the Hidaka-sanmyaku Erimo Quasi-National Park. The lake was named after nearby Mt. Toyonidake, though the name "Toyoni" derives from Ainu language meaning "a place with soil." Indigenous Ainu people originally called it "Kamuito," meaning "a marsh where a god lives," reflecting the spiritual significance they attributed to this remote location.

The lake remained virtually unknown to most Japanese until it gained sudden fame after appearing in a popular television commercial. What sets Lake Toyoni apart is its remarkable natural shape—when viewed from above, the lake forms a nearly perfect heart, earning it the nickname "Heart Lake." This 30-hectare emerald lake is one of the few naturally heart-shaped bodies of water in the world, with a perimeter of approximately 1 kilometer and a maximum depth of around 18 meters. The lake is surrounded entirely by dense virgin forest, which enhances its distinctive heart silhouette and provides a striking contrast between the deep blue-green water and the encircling wilderness.

The primary way to experience Lake Toyoni is through seasonal helicopter tours that operate from late September to late October, coinciding with the autumn foliage season. During this period, the surrounding forests transform from green to vibrant shades of orange, red, and brown, creating a spectacular frame around the blue heart-shaped lake. These aerial tours provide the only true perspective to appreciate the lake's unique geometry, as the heart shape cannot be fully perceived from ground level.

Visitors can also reach the lake shore via a 200-meter walk from the parking lot, though the terrain includes a scree slope with mossy rocks. A walking path of approximately 1.5 kilometers circles the lake, allowing ground-level exploration for those wearing appropriate hiking equipment. The lakeside entrance features a bench and public restrooms. The surrounding protected forest is home to diverse wildlife including brown bears, Yezo pikas (a rare mountain-dwelling mammal found only around Daisetsuzan Mountain Range), foxes, and various bird species. The lake contains rainbow trout and white-spotted char, making it a quiet fishing spot.

Access to Lake Toyoni requires careful planning. The lake is reached via Route 336, with signs marking the way along the forest road that follows the Sarutome River. This access road is unpaved and not maintained during winter months, making visits only feasible when there is no snow. By car, the lake is approximately 2 hours from Obihiro and about 4 hours from Sapporo. The nearest town, Erimo, can be reached via the Erimo Express highway bus from Sapporo, which takes approximately 3 hours and 45 minutes and requires advance reservation. From Erimo Town, visitors must drive to the lake. There are no direct public transportation options to Lake Toyoni itself.