Lake Okutama is not a natural lake at all. It is the reservoir behind the Ogouchi dam, completed in 1957 to supply water to Tokyo, and it fills a deep, narrow valley in the mountains at the western end of the city's territory. Several hundred families had to leave their homes to make way for the water, and the drowned villages, together with the old roads, lie somewhere beneath the surface. The lake is still one of the main sources of drinking water for the capital, so it is kept clean, the shores are wooded, and there is little building around it.
The road follows the shoreline, climbing and dropping around the arms of the reservoir, with tunnels, bridges and narrow bends. The altitude is about 530 metres, and in the cedar-shaded sections the air feels damp and cool. Across the water, the slopes rise steeply into forest, with the ridges of the Okutama mountains behind. Mount Kumotori, the highest point in Tokyo at 2,017 metres, lies farther on, and much of the surrounding country is a national park. In autumn the maples and oaks turn red and gold, and the lake reflects the colours.
This is a long way from the city centre. Itsukaichi and Ome, the nearest large towns, are seventeen kilometres away, and the road to the lake climbs steadily up the valley of the Tama river. Fill your tank before you start, as pumps are scarce in the mountains. Food is available in the small village of Okutama, where there are a few simple restaurants serving soba, grilled river fish and local vegetables, and a handful of inns. There are also vending machines at most parking areas, which is typical in Japan.
Riding here is a pleasure on a weekday and a slow crawl on a fine weekend, when motorcyclists, cyclists and day-trippers all head for the hills. The bends are tight and the road narrow, with limited visibility and some falling rocks after heavy rain, so go carefully. Wildlife is part of the setting: deer, monkeys and wild boar live in the forests, and bears are present, although rarely seen. The best time is early in the morning, when mist hangs over the water and the road is empty, or in late autumn, when the leaves are at their peak.