Nonaka Kofun sits quietly in the town of Fujiidera in southeast Osaka, one of the larger tombs of the Furuichi group, and unlike many of its neighbours it has a story that archaeologists keep returning to. When it was excavated in the 1960s, workers found huge amounts of weapons and armour inside and around the mound: helmets, iron arrowheads, swords and stacks of iron plate. The place seemed to be a kind of arsenal buried beside the tomb of someone powerful. It makes you think about what the fifth-century Yamato court considered precious.
The map labels the nearest town Kashihara, but you are really on the Kawachi plain, a low area between the Yamato river and the mountains, now thickly built up with suburbs. The tomb is a rounded, forested mound, and from above it forms the typical keyhole shape. It is not a showpiece like the giant tombs nearby; you walk around, read the sign and appreciate how the Furuichi group was woven into everyday life.
Riding here is plain city riding. Use the bike to hop between the tombs, and expect traffic, signals and the kind of narrow streets that make a big touring machine feel overdressed. There is no problem with fuel, as Fujiidera and Habikino and the other nearby cities have stations at every turn, and the convenience stores open all night.
Because the tombs lie so near each other, it is easy to build a route that gathers several in an afternoon, going from small to huge. Start with the humble mounds, then finish at the massive tomb of Emperor Ojin; the contrast teaches you more than the signboards.
If you can, come in spring or in late autumn. At the right hour in March the cherry blossoms dust the paths, and the whole district has the calm of a place that has made peace with its own antiquity. Summer is thick with humidity and noise from the cicadas, and the best advice then is to carry a cold drink and visit early.