Burial mounds usually dating to the 3rd to 7th-centuries can be found across Japan. While several types exist, the most curious formation is known to archaeologists as yokoana-bo, or “sidelong hole-style tomb.” The Hundred Caves of Yoshimi is a notable example of this configuration. There is another “Hundred Caves” in Utsunomiya City, but it’s not as well-known or preserved. The Nagaoka Hyakuana Burial Mound is believed to be a familial tomb originally constructed during the early 7th-century. It consists of 52 man-made caves (or “holes”) cut into the side of a…
