Bokor was built in nine months, and it cost roughly nine hundred lives. In 1921 French overseers drove Cambodian and Vietnamese labourers up a jungle escarpment in Kampot province to cut a road and put a retreat from the lowland heat on the plateau above, a thousand metres up. Malaria, dysentery, exhaustion and rockfall did the killing. What they made is still up there and mostly empty — and for months not visible at all. Monsoon air off the Gulf is forced up the escarpment and condenses, so the ruins fade into moving cloud and harden back out of it while you watch, often within a minute. The dry northeast monsoon strips that cloud off, the one window when the cliff edge behind the old casino opens onto the Gulf and the silhouette of Phu Quoc.
The building you walk into is the Catholic church, standing alone on open ground, render blackened, walls holed by gunfire, candles still on the altar. Those holes are not decay: someone cut one to shoot through. When Vietnamese forces invaded in 1979, Khmer Rouge fighters dug into the hill station and held it for months, using the church as a strongpoint, and they stayed on this mountain into the early 1990s. From there you pick your way across lichen-covered boulders to the old water tower on the skyline, far enough from the church to show how much the French built here. Wat Sampov Pram, the plateau's working temple, is packed with gilded Buddhas, painted disciples and naga serpents, candlelit in the damp while the fog presses at the doorway behind you. Late in the monsoon the Popokvil comes over the lip in a brown roaring sheet; in the dry months it is a bare rock staircase with a trickle down it. Out on the open heath the pitcher plant hangs its traps among the grass, vessels furred with silver hair that drown whatever falls in. A French collector picked the first ones here in January 1904; they sat in a Paris herbarium until 2009, when the species was finally described. It grows on this mountain and nowhere else.