The Izu Skyline runs along the backbone of the Izu peninsula, a toll road that follows the high ridge from the Atami area south toward the Amagi mountains, and the section near Ito is among the highest and most open. Here the road runs through grass and low scrub, with views both ways: east to the Pacific and Sagami Bay, west to Suruga Bay, and, on clear days, north to Mount Fuji. The peninsula is narrow, so it is possible to see both seas from one place.
Izu is volcanic in origin, a piece of the Philippine Sea plate that collided with Honshu and is still pushing into it. That collision is responsible for the hot springs, the earthquakes and the steep terrain of the whole peninsula. The ridge itself is made of old volcanic cones, now covered in pampas grass, which turns silver and gold in autumn and is wonderful in low sunlight. In spring, azaleas and wild flowers bloom along the roadside.
The road is well maintained, and the bends are smooth and open, ideal for relaxed riding. Because it is a toll road, traffic is lighter than on the coastal route, and on a weekday morning you may have long stretches to yourself. Cyclists use the road too, so keep an eye out. Fog is common at this height, particularly in spring and early summer, and it can reduce visibility sharply. The road may also close in snow or ice in winter, so check conditions before you go.
Atami lies in the other direction. Bring water and a snack, because the ridge is exposed and the only facilities may be vending machines at parking areas. Ito itself is an old hot spring town, linked to William Adams, the English sailor who became a samurai and built Japan's first Western-style ships here in the early seventeenth century, and a monument to him stands near the harbour.