Jianmen Pass is the centrepiece of the park: a narrow defile between two limestone cliffs so sheer and close together that the sky above narrows to a strip. The pass controlled the only practical route between the Sichuan basin and the north for two thousand years, and every army that needed to enter or leave Sichuan by land had to come through here. The fortifications, repeatedly built and destroyed over the centuries, have been reconstructed in a style that is theatrical but gives an adequate sense of the defensive possibilities.
The cliffs themselves are the real sight. The limestone formations rise to 800 metres in places, and the way the road threads through the gap — barely wide enough for a cart for much of its length — makes the strategic significance immediately legible. The Three Kingdoms associations are pervasive: information boards reference Zhuge Liang at every significant point, and the site is genuinely inseparable from that history in Chinese cultural memory, in the way that certain English landscapes are inseparable from Shakespeare or certain Italian ones from Dante.
A reconstructed section of the ancient plank road — wooden planks suspended from iron brackets set into the cliff face above the gorge — runs through the most dramatic section of the canyon. The original engineering, which allowed supply convoys to move through terrain where no natural road was possible, is visible in the holes drilled into the cliff for the bracket anchors. Walking this section gives the clearest sense of the civil and military achievement the road represented.