Although traditionally referred to as the "Izu Seven" (伊豆七島 Izu Shichitō ), there are in fact more than a dozen islands and islets. Nine among them are currently inhabited.
The Izu islands stretch south-east from the Izu Peninsula on Honshu and cover an area of approximately 301.56 km2 (116.43 sq mi). There are nine populated islands with a total population of 24,645 people (as of 2009) spread over 296.56 km2 (114.50 sq mi). The largest of them is Izu Oshima (8,346 inhabitants, 91.06 km2 (35.16 sq mi)), the smallest Toshima (292 inhabitants, 4.12 km2 (1.59 sq mi).) Of the inhabited islands, seven are traditionally referred to as the "Izu Seven": Oshima, Toshima, Niijima, Kozujima, Miyakejima, Hachijojima, and Mikurajima, though Shikinejima and Aogashima are sometimes included as well.Each of the island has its unique character: Oshima is noted for its active volcano Mt Mihara and camellias, Hachijojima for its former penal colony, Mikurajima for dolphin watching, Niijima for its numerous beaches, Kozujima for its white sandy shores, Hachijojima for its well-preserved unique culture, and Miyakejima for the 2001 volcanic eruption.
During the Edo period, Nii-jima, Miyake-jima, and Hachijō-jima served as places of exile for criminals.
The subtropical Ogasawara Islands, which are also administratively part of Tokyo, lie further to the south. They form a far-flung archipelago of over thirty (30) islands some 1,000 km due south of Tokyo.