Nakaoyama Kofun
A compact, three-tiered octagonal tomb linked by archaeological evidence to Emperor Monmu.
Verified site photographs are being prepared.Discover Nakaoyama Kofun
Nakaoyama Kofun is a small hilltop tomb with an unusually elaborate outline: an octagon built in three tiers, with stonework and paved rings around its base. Its burial chamber is a tiny, carefully polished stone vault for cremated remains, a design that marks a shift from older burial customs. Nara Prefecture considers the tomb highly likely to be the mausoleum recorded for Emperor Monmu, based on its location, date and cremation burial; the identification is a strong archaeological interpretation, not an inscription naming him. The mound is an outdoor heritage stop near Takamatsuzuka, where the contrast between a painted burial and this compact octagonal form helps explain the variety of Asuka's late seventh-century elite tombs.
Look for the eight-sided profile
Nara Prefecture describes a three-tiered octagonal mound, built with rammed earth and stone revetments. Its opposite-side span is about 19.5 metres and its height exceeds four metres. The octagonal plan, rather than a broad monumental mound, is the feature to look for from the permitted public route.
Use the marked approach
Follow current on-site signs to the public approach. The octagonal mound and chamber are protected cultural property; do not leave the marked path or enter the burial chamber.
Read the stone rings around the base
The prefecture's archaeological account records three concentric paved bands around the mound, with the outer band spanning at least about 32.5 metres. Lower tiers combined foundation stones and carefully placed stones; the upper tier was shaped from rammed earth. This layered construction helps explain the engineering behind a late Asuka octagonal tomb.
Understand the small burial chamber
The burial space is a side-entry stone vault assembled from ten cut stones, roughly 90 centimetres in each dimension. Its walls were polished and coated with vermilion; a shallow recess in the floor is interpreted as a support for an urn containing cremated bones. The chamber is not presented as an interior visitor attraction. Appreciate it through the archaeological record and protect the mound by staying on the marked path.
Connect the tomb with Emperor Monmu carefully
The village and prefecture relate the tomb to the record in Shoku Nihongi describing the burial of remains at Hinokuma no Anokami no Misasagi. Nara Prefecture says the location, structure and cremation evidence make Nakaoyama a highly likely match. Its historical association with Monmu is longstanding; keep the wording at 'highly likely' rather than certain.
Pair it with the Takamatsuzuka area
Nara Prefecture's tourism listing estimates a 20-minute walk from Kintetsu Asuka Station and publishes the Asuka Management Center contact. Separately, Asuka Tourism Association's 2026 volunteer-guide programme includes a 4.4 km Asuka Station loop via Iwayayama, Kengoshizuka, Takamatsuzuka and Nakaoyama. The published programme runs 15 August–20 December on Tuesdays, Fridays, Saturdays and Sundays; start times are around 09:00 or 13:00 depending on the route, each group is capped at 10, and advance booking is required. The guide fee is ¥1,000 per person, with admission and transport extra. Confirm the actual date, route and availability with the association (0744-54-3240); this is a guided loop, not the direct walk time to Nakaoyama. The sources reviewed do not confirm chamber entry, toilets, admission or parking at the mound itself.
Keep differing survey measurements distinct
An older Asuka Village cultural-property page describes a roughly 30-metre span and two rings of paving, while Nara Prefecture's record updated in 2026 gives a 19.5-metre opposite-side span and three outer paved rings. This guide follows the newer prefectural summary and keeps the variation visible; the figures may reflect different survey phases and definitions, so they should not be combined.
What to look for
Three-tiered octagonal mound
A rare, compact shape associated with the end of the Asuka period.
Cremation-era burial architecture
A polished stone vault designed around an urn for cremated remains, described through archaeological records rather than visitor entry.
A likely mausoleum of Emperor Monmu
Archaeologists consider the identification highly probable, while preserving the distinction between evidence and certainty.
Photo notes
No MyNara-licensed site photograph is attached. The village and prefecture source images have not been copied. Photograph only from public paths, follow posted rules and avoid entering protected archaeological features or private land.
Make a day of it
Explore guides close to this map point, then check the actual route before travelling. Distances below are straight lines, not walking distances or travel times; map points may not be entrances.
Sources & editorial status
Original MyNara draft based on the linked sources. Sources reviewed 24 October 2026. Opening arrangements, prices and offers may change; use the operator's current information before travelling.
- Nara Prefecture cultural-resource record — dimensions, structure, cremation burial and Monmu interpretation; updated 27 February 2026
- Nara Prefecture tourism guide — address, station walk and Asuka Management Center contact
- Asuka Village — designated historic-site record and earlier excavation details
- Asuka Tourism Association — current seasonal route via Nakaoyama, dates, fee, duration, and advance booking
- Asuka Village tourism site — ancient tomb directory and Takamatsuzuka area context