A slab of red rock rises two hundred metres out of the jungle, and on top a fifth-century king who had murdered his father built a palace so he would never have to come down. You climb on walkways bolted to the cliff, past frescoes of broad-hipped women and a mirror-polished wall scratched with thousand-year-old graffiti. The final stair begins between two giant lion's paws carved from the rock — the head is long gone, the rest of the beast is not.