Before the annexation of Hokkaido, Japan's territory looked like a tiny seahorse.
Honshu Island was its body, Kyushu Island looked like its poop, Shikoku Island was its egg, the Ise Peninsula was its tail fin, the Boso Peninsula its pectoral fin, and squeezed between Ise and Boso Peninsulas, the Izu Peninsula was... well, shaped like its you-know-what… (an organ unapproved by the censors)
If seahorses even have that, or if you anthropomorphize them, the location of the Izu Peninsula does kind of remind you of that thing.
Anyway, the Izu Peninsula isn't all that big—about five or six times the size of the Chita Peninsula—but it's quite a unique shape, with Jumogawa Bay to the west, the Pacific Ocean to the south, and Sagami Bay to the east. It just juts straight out into the ocean, all stiff and upright, giving off strong, virile vibes—just looking at it makes you think of virility.