Unfinished stele of Yangshan

The three pieces of the Yangshan stele: base (~30.35 m x 16 m x 13 m, estimated mass ~16,250 t), shaft (~49.4 m tall, 10.7 m x 4.4 m, ~8,799 t), head (~10.7 m tall, 20.3 m x 8.4 m, ~6,118 t). Total assembled: about 73 m in height and ~31,000 tonnes. The largest monolith ever carved by humans if the volumetric estimates are correct. Note: the mass figures vary by source — no official open-access publication has been able to settle the matter definitively.

Commissioned by Zhu Di (Yongle, r. 1402-1424), 3rd son of the Ming founder, for the mausoleum of his father Zhu Yuanzhang (Ming Xiaoling, Nanjing). Around 1413, a substitute stele 8.78 m tall (Shengong Shengde, "Divine Merits and Sacred Virtues") was installed on the tomb — indirect evidence that the Yangshan project had been abandoned by that date.

Documented carving technique: rows of holes drilled with an iron chisel, then wedges driven in simultaneously (straight-line cleaving); dry wooden wedges soaked with water (progressive expansion); thermal shock (fire + cold water) for difficult cleavage planes. Listed on the Jiangsu provincial register of historical monuments as early as 1956.