Phnom Sorsia stands about eighteen kilometres east of Kampot city, reached by a dirt track that leaves National Highway 33 and runs out through the paddy. From a distance the hill does not look like a hill so much as a mistake — a wooded lump of grey rock shoved up out of dead-flat rice fields, with nothing between it and the next one but water and green. These are karst towers, the eroded remnants of an ancient limestone seabed, and southern Cambodia is dotted with them. Water has been working on their insides for far longer than anyone has been climbing them, hollowing out chambers, stalactites and passages. From the summit of Sorsia there is no drama at all in the view, just rice in every direction to the horizon, which is exactly what makes standing up there feel like standing on the deck of something.

The main cave is called Rung Damrey Saa — the White Elephant's Cave. Its stalagmites, pale and rounded and heavy at the base, are read as a herd of white elephants, and one formation is taken for the head of a single animal. The naming is not casual. In Theravada Buddhist tradition a white elephant appeared to Queen Maya in the dream that announced the Buddha's conception, and across mainland Southeast Asia the possession of a white elephant marked a king as legitimate and his reign as blessed. To find one asleep in the rock, made by dripping water over tens of thousands of years, is the sort of coincidence that turns a cave into a shrine. Two Buddha statues sit to the right of the entrance. A pool of cool water lies concealed deeper in, reached through a hole in the stone.

Phnom Sorsia is a holy hill, and it has been shaped accordingly. Steps have been cut into the slope in a long winding line, branching to reach both the White Elephant Cave and the summit, where a stupa stands. There is a temple partway up, painted in the loud, saturated colours that Khmer religious buildings wear without apology — reds and golds and sky blues that would look garish anywhere else and look entirely correct here. The signage at the road, in the flat optimism of Cambodian tourism promotion, calls the whole thing the Phnom Sorsia Resort. There is no resort. There is a hill, a staircase, some caves, a temple and a stupa, which between them are worth considerably more than the sign promises.

Sorsia is one stop on a circuit rather than a destination in itself, and the circuit is the point. Eight kilometres northeast of Kampot, Phnom Chhnork holds a small brick temple to Shiva built in the seventh century, in the Funan period, standing inside a cave mouth and reached by its own stone steps — roughly thirteen hundred years old and still under a limestone roof. Further east, the caves at Kampong Trach draw swimmers into collapsed chambers open to the sky. The pattern repeats across this corner of Cambodia: wherever the rock rose out of the rice, people climbed it, went inside, and left something behind. Hindu first, then Buddhist, and in the case of Sorsia's bat cave, something older and more practical than either.