Zonguldak is one of the major centers for coal production in Anatolia and also an important port on the Black Sea.
Zonguldak was established around 550 BC by people from Doric clans with the name as Mariandyn. Around 560 BC, people from Megara and Boiotia came to establish a strong Greek colony there changing its name as Herakleia Pontika, based on the mythical hero of Ancient Greece Heracles. As time passed by, the Greek name "Heracles" became "Eregli" among people.
The city of Zonguldak, which was dominated by the Kingdom of Bithynia during the 2nd century BC, is a very strategic area due to its abundant coal mines and harbor. It was largely occupied by Romans in the first century AD with some control transferring to Byzantine, Genoese and Ottoman Empire. France captured it following World War I but gave it back in 1920 when suffrage for Turkey became successful following that war.
Zonguldak has some of the most beautiful beaches in Turkey. Some of those include Kopuz and Uzunkum, where you may choose a tea garden or restaurant for your lunch break, watch the scenic surroundings, photograph nature-lover photography.
Eregli, which is located 37 miles west of Zonguldak, is home to a mythic site from ancient Greco-Roman times. Not far from the town, near Kavakderesi and below Cehennemagzi Hill with its entrance to the underworld, Hercules supposedly captured Cerberus—the three-headed dog guarding both gates of heaven and hell. When you visit enjoy some delicious strawberries; they are among the best in the world.