Topping the karst limestone mountain of Nemrut Dagi (2150 meters / 7056 feet) in the south-eastern region and towards Taurus range, 90 kilometers (56 miles) north-east of Adiyaman, is the Hierothosion of the Kommagene King Antiochus I (69-38 BC), dedicated to his own glory and that of the gods.
Antiochus' tomb is concealed somewhere inside the 50 meters (164 feet) high man-made burial mound, with its spectacular terraces on three sides (east, north and west). The 80 meters (260 feet) long north terrace, lined with (collapsed) columns, served as a place of assembly and arena for processions and other rituals.
On either side of the east terrace stand relieves of the King's ancestors, paternal (Persian) to the north, maternal (Seleucid) to the south, framing the colossal figures of the gods' heads standing on the ground facing the main altar. These include, in addition to eagles and lions, the Greco-Persian mixed deities Zeus - Oromasdes, Hercules - Verethragna - Artagnes - Ares, Apollo - Mithras - Helios - Hermes, and Kommagene - Tyche, as well as Antiochus I himself.
A similar arrangement is repeated on the west terrace, which is some 10 meters (33 feet) lower than the east. Here the heads of the colossal statues are better preserved and there are also more of them. The "Lion Horoscope" with its astral motifs symbolizes the deification of Antiochus I through the metamorphosis of king into star.
The ruins of Samosata (3rd century), the old Kommagene capital on the Euphrates, now mostly lie submerged beneath the waters of the Atatürk Baraji (Dam) south-west of Kahta. Only when the level in the reservoir is low does the 45 meters (148 feet) high castle hill, which in 1990 was still being excavated, break the surface of the water. The site is reached from Adiyaman by driving east to Anil and then south along the new road to Yeni Samsat (about 65 kilometers / 40 miles). From about 640 AD Samsat, like Adiyaman, was one of the frontier forts (thugur) constantly changing hands between Byzantium and the Arab and Turkoman invaders, sometimes under Christian occupation (e.g. 700, 860, 1098) and at other times Muslim (10th century Emirate of Aleppo; 12th century Seljuks).
Arsameia on the Nymphaios
Approximately 25 kilometers (15 miles) north-east of Adiyaman, above the east bank of the Kahta Çayi (Nymphaios) opposite Yeni Kale castle near Eski Kahta (see below), is a cult and burial site known today as Eski Kale (Mithridates I Kallinikos) and the summer residence of the Kommagene rulers founded in the 3rd century BC by Arsames. In addition to the remains of steps and buildings on the summit plateau (mosaics from the 2nd century BC), a number of relieves and rock chambers are passed on the approach. Lower relief (II): the god Mithras - Helios (a further part depicting Antiochus II is missing); middle relief (I): (fragments) Mithridates and his son Antiochus I, antechamber (cult site of the god Mithras) with, to the rear, a rock tunnel with fourteen steps leading to the burial chamber of Mithridates (most probabily); upper relief (III): Dexiosis relief of king (Mithridates or Antiochus I) with the demigod Hercules (extending his right hand), inscription by Antiochus I, steeply-stepped, blocked, rock tunnel (158 meters / 518 feet deep), purpose unknown.
Cendere Koprusu (Chabinas Bridge)
This well-preserved Roman bridge crossing the Cendere (the ancient Chabinas) at a point where the river emerges from an impressive gorge into the wide valley of the Kahta Cayi, was built between AD 198 and 200 by the "legio XVI Flavia firma", stationed in Samosata (Samsat). According to an inscription four Kommagene towns financed the building of the single-arched bridge with its span of 34.2 meters (112 feet). One of the original four dedicatory columns (to Septimus Severus, his wife lulia Domna and their sons Caracalla and Geta), the one to Geta, was taken down in AD 212, part of an attempt to obliterate any reminder of Caracalla's having had his brother and co-ruler removed.
The Dikilitas tumulus, 6 meters (20 feet) high and 35 meter (115 feet) in diameter, located 60 kilometers (37 miles) south-west of Adiyaman, is almost certainly the burial place of Mithridates II of Kommagene and his wife. Of the three original pairs of columns (from which the old name Sesonk = "three columns" was derived) only the southernmost survive complete with linking architrave. The outer chamber, with three tombs, is accessible. If driving there the best route, which even then is not without its problems, is via Sambayat, Besyol and Zormagora (4 kilometers / 2.5 miles on foot).
Eski Kahta (Yeni Kale)
The village of Kocahisar, 70 kilometers (43 miles) north-east of Adiyaman, is a convenient spot from which to visit the Mameluke fortress of Yeni Kale, built on a narrow mountain spur high above a Seljuk bridge spanning the Kahta Cayi gorge. The complex was constructed on top of earlier foundations by Kara Sonkar (Governor of Aleppo, 1286), being altered and extended at the end of the 13th century and in the mid 14th century. Water was brought up from the Kahta Çayi via a stepped passage-way and stored in a cistern. For the "express" delivery of messages carrier pigeons were used, notably during Sultan Kala'un's decisive battle against the Mongols at Horns (1281).
Göksu Koprüsü (bridge)
A short distance east of Dikilitas are the remains of a triple-arched bridge (center arch, 31 meters / 102 feet, collapsed) over the Göksu, the ancient Singas, a tributary of the Euphrates. Up until the Middle Ages this was an important river crossing on the former military road from Samosata to Zeugma (60 kilometers / 37 miles south-west of Adiyaman).
Kahta (formerly Kolik), 35 kilometers (22 miles) east of Adiyaman, is the principal town of the district and the starting point for the drive through ancient Kommagene. Being short of hotel accommodation it has found itself increasingly eclipsed by the provincial capital.
Karakus Tepesi (Hill)
This Kommagene tumulus 47 kilometers (29 miles) north-east of Adiyaman was erected by Mithridates II (36-20 BC) for his mother Isias, his sister Laodike (36 BC, wife of the Parthian King Orodes IV), and his niece Aka. From the original three pairs of columns only four now survive, the southernmost being crowned by an eagle (Karakus = "black bird"), the north-easterly one by a bull. On the north-west side are a toppled lion and a column the inscription on which records details of the tomb.