The martyrs of Unzen
Many Christians were tortured and killed at Unzen, a place of numerous burning hot springs
In Unzen on the Shimabara peninsula, there are numerous burning hot springs which are referred to in Japanese as jigoku (literally, "hells"). These were once used to torture Christians as a way of trying to force them to renounce their faith. Just as Christ offered himself up on a cross for the world’s salvation, so too did the martyrs of Unzen willingly give up their lives in imitation of their crucified Lord.
In Arima (where Christians were also high in number), a record remains suggesting that eight people were sentenced to being burnt at the stake at Arima river.