Overlooking the plain around Battambang, the limestone outcrop of Phnom Sampeu owes its name to its odd shape, reminiscent of a sampan from afar. Its summit offers a spectacular 360° panorama of the surrounding area. A fact that prompted the Khmer Rouge to establish a bastion here to execute their victims and then throw them off the top of the cliffs. Two caves, now known as the Killing caves, half-way up the hill, served as prisons. One has since been converted into a memorial.