This is the Oito jigoku. According to local legend, there was once a poor woman named Oito who lived close to Shimabara Castle in the late 1800s. Oita was accused of killing her husband with the help of her secret lover, and she was found guilty and sentenced to death. At the moment of her execution, a jigoku came bubbling up from beneath the earth. The word “jigoku” carries the double meaning of “hot spring” and “hell,” indicating Oito’s eventual fate.
Monument to Christian Martyrs
On the hill above Oito Jigoku is the kirishitan junkyō-hi, or the Monument to Christian Martyrs. The simple cross erected there during the Meiji era (1868–1912) commemorates the approximately 33 Christians who were tortured and killed in Unzen between 1627 and 1630.
Christianity was brought to Japan in the mid-1500s and flourished in Kyushu. Nagasaki became a stronghold of Christian faith, and the lord of the Shimabara Peninsula, Arima Harunobu (1567–1612) converted in 1579.
Christianity was popular for several decades in Kyushu and across Japan, but by the early 1600s the fortunes of this foreign faith changed. While embracing Christianity was originally seen as a necessary step in establishing relations with the Europeans and subsequently gaining access to firearms and other trade goods, the religion came to be seen as a gateway to colonization by hostile foreign powers. Missionaries were exiled, converts were executed, and the religion itself was banned.
Beginning in 1627, dozens of Christians brought to Unzen from across the Shimabara Peninsula were tortured in the jigoku until they renounced their faith. Most did not, and it is this sacrifice that inspired the people of Unzen to commemorate the victims’ strength of belief shortly after the ban on Christianity was lifted.
　Are you hungry? On your left, steam from the jigoku is funneled through a clay pipe and used to cook “onsen eggs.” This delightful snack has been popular with tourists for more than 100 years. But make sure the brave cats that like to hang out by the jigoku do not take your meal!
　Farther along the boardwalk is the Oito Jigoku. According to local legend there once was a poor woman named Oito who lived close to Shimabara Castle in the late 1800s. She was accused of conspiring with her lover to murder her husband and was executed for her crimes. At almost the same time, this jigoku came bubbling up from beneath the earth. The jigoku was given Oito’s name as a reminder of what could await those accused of infidelity and murder in the afterlife.