The massive rock tombs of the Pontic kings are carved into the cliff-face on the northern bank of the Yeşılırmak. There are two main clusters of tombs, and bearing right from the Kızlar Sarayı will bring you to the most accessible group, as well as to a café and toilet. You may want to clamber up inside some of the tombs through the raised stone doorways, but if you find the doorways padlocked you will need to rouse the site guardian to open them. Passages cut out of the rock run behind two of the tombs and you can only marvel at the work that must have been involved in excavating them. Bearing left will bring you to two larger tombs; beside the entrance to one of them is the mouth of a tunnel, thought to lead to the river. More tombs can be found with a bit of effort – there are a total of eighteen throughout the valley.