Noto Peninsula, peninsula in Ishikawa ken (prefecture), Honshu, Japan, jutting into the Sea of Japan and enclosing Toyama Bay. The largest peninsula on the northern Honshu coast, it extends northward for 50 miles (80 km) and has a width of about 19 miles (30 km). The peninsula is separated from mainland Honshu by the Lake Ōchi graben (a depression of the Earth’s crust bounded by faults). The peninsula’s mountainous interior is similar to that of Sado, an island to the northeast.
The Noto Peninsula has been settled since ancient times, and there is evidence of early contact with the island of Tsushima and with northern Korea and Manchuria. The town of Wajima, at the peninsula’s northern tip, is known for its women pearl divers and its production of elaborate lacquer ware. Parts of the peninsula were designated national park land in 1968.