6 Best Sights in The Black Sea Coast and Lake Van, Turkey

On the tranquil, uninhabited islet of Akdamar, among the wild olive and almond trees, stand the scant remains of a monastery that include the truly splendid Church of the Holy Cross. Built in AD 921 by an Armenian king, Gagik Artsruni of Vaspurakan, the compound was originally part of a palace, but was later converted to a monastery. Incredible high-relief carvings on the exterior make the church one of the most enchanting spots in Turkey. Much of the Old Testament is depicted here: look for Adam and Eve, David and Goliath, and Jonah and the whale. Along the top is a frieze of running animals; another frieze shows a vineyard where laborers work the fields and women dance with bears; and, of course, King Gagik, almost hidden above the entrance, is depicted, offering his church to Christ. The monastery operated until WWI, and since 2010 annual religious services have been allowed, usually in early September.

There are a handful of small cafés and gift shops on the island, and a few coves that offer the opportunity to swim in the alkaline lake. One of the most charming things about the island may be the large number of gray rabbits scampering about. To reach Akdamar from Van, take a minibus (20 TL) or follow Route 300 to Gevaş, which is about 20 miles away. Just past Gevaş, you'll see ferries waiting at the well-marked landing to collect the required number of passengers—between 10 and 15—for the 20-minute ride. Normally it costs 30 TL per person but if there aren't enough passengers the round-trip is around 300 TL. Boats return to the mainland hourly until 6 pm.

The Romans left a strong mark on Diyarbakır—not only did they lay the foundations for its famous city walls, but they created the basic layout of the old town: a rough rectangle with two main streets that cross and connect the four gates that are found at each compass point. The walls were constructed by the Byzantine Emperor Constantius in the 4th century and various Arab and Turkish rulers restored and added to them over the centuries, until the local Artukid Turcoman emir al Malik al-Salih Mahmud gave them their current form in 1208. On the whole, the walls remain in good shape along their entire length; indeed, if you feel like a bit of an adventure, the best way to appreciate these great walls is to wander along the top. Of the original 72 towers, 67 are still standing, decorated with myriad inscriptions in the language of every conqueror and with Seljuk reliefs of animals and men; you can also explore their inner chambers and corridors. In 2015, the walls became a UNESO World Heritage sight, along with the surrounding Hevsel Gardens, the greenbelt between Diyarbakir and the Tigris River.

Erected around 9,000 BC, 6,000 years before Stonehenge, before even the invention of agriculture, this series of stone circles on a hill 15 km (9 miles) northeast of the town of Urfa have been popularly declared the "World's Oldest Temple." The stones' purpose has been subject to wide interpretation: some believe this was a burial site; others, a place of ritual initiation, or that each circle belonged to a different tribe that gathered here for ritual and trade. What is clear, though, is that no one lived here, and that it would have taken hundreds of people to transport and erect the pillars. The site consists of a series of circles and ovals formed by large T-shaped pillars of equal height, usually with two larger pillars inside. The pillars are thought to have held a roof. Many of the outer surfaces are carved, some are anthropomorphic, others depict the savage nightmares of a hunter-gatherer's life, such as snakes, foxes, vultures, scorpions, and wild boar. Most curiously of all, the structures were deliberately buried when the site was abandoned. Four structures have been exposed since excavations began in 1995, and another 16 have been identified by geophysicists; excavations continue in spring and fall. The circles themselves are off-limits and enclosed by low fences, but visitors are welcome to follow pathways from which all are clearly visible. Take the old highway the D400 east from Şanlıurfa and look for the marked turning on the left just as you leave the built-up area. This road continues about 15 km (10 miles), crossing over the new highway. Shortly after this is a turn, left for the last few miles up the hill to the site. Alternatively, a return taxi (including waiting time) from Urfa should cost around 80 TL. While the site is open year-round, many of the pillars are covered in winter in order to protect them from the elements.

On the shore of Lake Van, the remains of the small town of Ahlat are an impressive open-air museum of what was an important cultural destination. The remains of Seljuk and Ottoman mosques and fortresses, and the medieval cemetery with its impressive collection of monumental türbe (tombs), are the main attractions. A small museum on the sprawling site contains a collection of Uratian metalwork and pottery.

The inner castle of Diyarbakır's old town is a circular fortress that once held the city's palace and other important buildings. Beside it stands the 16th-century Hazreti Süleymaniye Cami, which contains the grave of the son of Khalid ibn al-Walid, the companion of the prophet Muhammad who died during the city's capture. It has a tall, graceful minaret and is striped with black basalt and pale sandstone, a favorite design of this city's medieval architects. Its courtyard fountain is fed by an underground spring that has supplied cold, clear water to the city for 5,000 years. It has undergone extensive research in recent years and now holds the city's fantastic Archaeological Museum in one of the renovated court buildings. There's also an Atatürk Museum (as it seems no Turkish city is complete without one) and the early Byzantine Church of St. George, which with its two impressive domes is worth a visit.

Steps—considerably fewer than the 1,000 claimed in local tourist handouts—ascend to Van Kalesi, the sprawling Urartian fortress on the outskirts of town. A path branches right to Urartian tombs in the sheer south rock face; an impressive cuneiform inscription here honors King Xerxes, whose Persian troops occupied the fortress early in the 5th century BC (look for the red metal fence on the southeast side).You may need to pay a local a tip to show you these. The crumbling ramparts are still impressive (more so than the parts that have been heavily restored), but as is often true in these parts, it's the view—sweeping across the lake and mountains—that makes the steep climb worthwhile. A taxi from the new town should cost no more than 30 TL one way. Cheaper dolmuş (shared taxis) depart regularly from the north end of Cumhuriyet Caddesi and are marked "Kale."