Gaziantep, or informally known as Antep, is a city in Southeastern Anatolia.
Set in western reaches of Southeastern Anatolian plateau, Gaziantep is a surprisingly large (with a population of almost 2,000,000) and modern city.
Gaziantep Airport. 15 km from city center. You can reach the city center from the airport with the Havaş shuttle service (9 lira, departs after most incoming flights)
The bus station (otogar) of the city is quite a few kilometers out of town. It is connected to city centre by local public buses, which cost 0.95 TL one-way. The bus from Sanliurfa takes 4hrs and costs 25TL (Aug 2012).
While Toros Express coming in from Istanbul via Konya and Adana was suspended in 2008 (and it is not certain when and if it will resume service), Turkish State Railways put a weekly passenger train service from Gaziantep to Mosul in northwestern Iraq recently, which crosses a short strip of Syrian territory. It departs from Mosul at noon every Tuesday and arrives in Gaziantep 5:40AM the next day, and costs €25 pp. (Update, Aug 2010. Mosul service has been suspended until further notice.)
There also twice weekly trains connecting the city to Aleppo in Syria. From Aleppo, trains depart at 5AM on Tuesdays and Fridays, arriving in Gaziantep five hours later. From Gaziantep, they depart at 8:30PM on Tuesdays and Fridays and arrive five hours later in Aleppo, at 1:29AM after midnight. The trip costs €12.75 pp one-way.
The city centre is reasonably compact and walkable. There are plenty of local buses if you prefer and of course taxis for tired feet.
Visit the castle, explore the bazaars and don't forget the museum. There are a lot of museums in the center of city, especially some of them are close to castle. You should go Mosaic Museum (close to stadium), Medusa Museum (Glass Museum), Martyr's Museum, Dervishes Museum (Mevlevihane), Hasan Süzer Etnographia Museum.
You can buy a lot of traditional things in Gaziantep. You should try Bakırcılar Çarşısı, a traditional bazaar in the center of the city. You can buy baklava, nargile (hooka pipe), yemeni (local leather shoes) and much more...
As the centre of a large pistachio-growing region, as the groves along the highway leading to Gaziantep indicate, you can find many stores selling this local product (known in Turkish as Antep Fıstığı, i.e. "Pistachio of Antep", an expression which surpassed the former name of Şam Fıstığı, i.e. "Pistachio of Damascus", used during Ottoman period), both fresh (not very tasty, though) and also in a salty roasted variety (a lot more delicious!).
Antep is known for its cuisine that is heavily influenced by its southern neighbours. The city is renowned for its local variety of kebab (Antep kebabı). You can find many places that sell spicy kebabs here. Make sure you enter a place that is crowded and order ayran with your kebab. Try a lahmacun, which is minced, marinated, spiced meat with minced vegetables on an extremely thin, crunchy dough. Lahmacun can be made with garlic or onions, in general, you will find garlic ones in Antep.
Antep is also famous for its pistachios. You can find fresh, unroasted pistachios as well as roasted ones. Try the spicy nuts.
Upon finishing your dinner, make sure to have baklava made with pistachios. Also, you can try the hot desserts with a scoop of ice cream on top.
Antep is known for its food, and meals there are one of the highlights of visiting the region. So enjoy yourself.
Many of Antep's drinking establishments are basically for picking up women. However there are some nice birahanes ("beer-houses") where you can enjoy a quiet drink in peace.
From city's otogar you will find numerous agents selling tickets to dozens of destinations including Istanbul, Konya, Van, Dogubeyazit, and Antalya to name a few. Buses leave frequently. Shop around for the best price. Bus to Marsin takes 5 hrs and costs 25 TL .