Use the Iiyama-side approach
The tourism bureau's October 2026 update says construction and closure on the Nozawa Onsen side will continue at least through the end of fiscal 2026. Navigation suggestions do not override the closure.
Check activities separately
The lake is known for spring flowers, summer scenery and autumn colour. Boat, fishing and activity operations vary by season and year, so confirm the specific provider before travel.
Drive slowly around visitors
Expect walkers and photographers near the lakeside. In winter or early morning, check snow clearing and ice before entering smaller roads.