Of all Tokyo¡¯s backstreets, the most remote await exploration on the city¡¯s outlying islands.

The largest and closest of these, Izu Oshima, beckoned to me this spring, a green gem set in an azure sea. I reserved the high-speed Jetfoil from Tokyo Takeshiba Terminal, which I¡¯m told ¡°flies¡± to Oshima in one hour and 40 minutes, provided the weather behaves.

Wind snaps nautical flags and swipes passenger¡¯s hats as I board the Tairyo, which is emblazoned with a giant rising sun, illustrator Ryohei Yanagihara¡¯s (1931-2015) jaunty take on Japan¡¯s Maritime Self-Defense Force flag.