Kofun come in various sizes, some large, some small. The largest in Japan is the Nintoku-tenno-ryo Kofun. It is 486 meters long! (486 meters is about ten double lengths of a 25-meter swimming pool. That's really long!) To construct such huge kofun, thousands of people are said to have been gathered from surrounding areas.
How to construct a large kofun (an example)
(1) Level the land on the scheduled site of the kofun.
(2) Measure distances and lay out ropes, based on a designdrawing.
(3) Dig a moat, and pile up the excavated earth to form a mound.
(4) Line the mound with stones to prevent it from collapsing andto make it look magnificent (if white stones are used, they will shine when light shines on them).
(5) Dig a hole at the top of the mound, and build a stonechamber inside it.
(6) Place haniwa clay figures side by side on the mound andbanks.
(7) Finally, bring in a stone coffin and place it inside the stonechamber.
Various different materials were needed to construct a kofun. These included soil to build up the mound, stones to lay on the mound, clay to make the haniwa and firewood to fire it. Moreover, various ingenious techniques were used. For example, the earth was not simply piled up; instead, layers of dry earth were alternated with layers of heavy, clay earth to prevent the mound from collapsing.
Ropes being laid out according to a design drawing
