Is Himeji Castle haunted?
Japan Reported haunting level 3 of 5

What actually happened
The city records the fortress founded by Akamatsu Norimura in 1333, rebuilt by Toyotomi Hideyoshi in 1580 and rebuilt again by Ikeda Terumasa between 1601 and 1609 into the five-storey keep that survives.
The history
The main keep was designated a National Treasure in 1931 and again in 1951, and the castle became a UNESCO World Cultural Heritage site in 1993.
What people report
The city's own guide says Okiku's Well is where the maid Okiku of the Banshu Sarayashiki tale is said to have been killed and thrown in over a missing plate; the city's research centre notes the well was probably named for the legend when the castle opened to the public in the Meiji era.
That paragraph is reported tradition, not a claim about what is there. The history above it is sourced; the stories are recorded because people tell them.
Visiting
68 Honmachi, Himeji, Hyogo 670-0012, Japan