Wat Kiri Sela Kep

This Buddhist temple sits at the foot of Phnom Kompong Trach, a dramatic karst formation riddled with more than 100 caverns and passageways. From the wat, an underground passage leads to a fishbowl-like formation, surrounded by vine-draped cliffs and open to the sky. Various stalactite-laden caves shelter reclining Buddhas and miniature Buddhist shrines. The temple is in Kompong Trach, 25km northeast of Kep. Take the dirt road heading north from the centre of town for 2km. At the wat, note that friendly local kids with torches (flashlights) are keen to put their evening-school English to use by serving as guides. Tip them if you use them.

If you're planning to do any serious spelunking, pack a headlamp and take a guide.