According to Jayne Hitchcock, who has written a book on the topic, Okinawa, Japan is crawling with ghosts.
Of the former Naha Air Base (pictured ca. 1966), she writes, "A U.S. military base gate on Hwy 58 (rumored to be the old Makiminato gate 2) used to have a frequent visitor, a GI from WWII. Each Friday and Saturday night at the same time, the GI in full combat gear would approach the gate, which was manned by Marines. When he reached the gate guard, he had a cigarette in his hand and would ask, 'Gotta light?' After the gate guard lit the cigarette, the GI would disappear into thin air. When this happened many times, Marines refused guard duty at this gate and it was finally closed. One theory about why the GI showed up every weekend is that sometimes when people die, their images are caught in a kind of time warp 'record player.' A certain thing could trigger this record player so that an event the person did when they were alive is replayed. Some say if you go to the area where this gate used to be you can still see the GI ask for a light, even though the guardhouse is no longer there."
Since the book's second edition, which was published in 2000, the story has morphed a little, and the ghost now wears a "bloody uniform," and is said to appear at Camp Hansen's Gate 3.
Hitchcock's book includes stories about Kadena Air Base, including ghostly Japanese marchers from World War II, and a house (now used for storage) that apparently hosts several different ghosts, including a woman washing her hair at the sink, a samurai riding a horse, and the voices of several children laughing or crying.