Ephesus is discovered in Selcuk, Izmir in western Turkey.
Kusadasi is 19 km. far away from Ephesus and Pamucak beach is 5 km far away from Ephesus. The original site of Ancient Ephesus was most likely established on the Aegean coast, on the shores of that sea which is today located 8 km. away from the archaeological excavations.
Over the centuries, in fact, the rubble brought on to the plain of the "Kucuk Menderes" has enlarged the alluvial plain surrounding the archaeological zone, leaving behind in actual fact the shores of the Aegean. In Roman times it was situated on the northern slopes of the hills Coressus and Pion and south of the Cayster (Kucuk Menderes) River, the silt from which has since formed a fertile plain but has caused the coastline to move ever farther west. In Roman times a sea channel was maintained with difficulty to a harbor well west of Pion. By late Byzantine times this channel had become useless, and the coast by the mid-20th century was three miles farther west.
Ephesus (Efes) is close to the town of Selcuk about an hour drive south of Izmir. Kusadasi is the nearest larger town, about 20km from Ephesus.
Ephesus was constructed on a river bend, that was eventually dredged into a full harbor near the mount of the Cayster River, on the western coast of Asia Minor (modern Turkey). Along the coastal plain between Smyrna to the north and Miletus to the south, the site is now about six miles from the Aegean Sea. The city shifted in five distinct locations over time, each within a small area. The Apostles Paul and John were familiar with the city that scholars have dubbed "Ephesus III" the largest (in area) of the five.
The areas where Ephesus located on as follows:
Ephesus I: Aya Suluk (St. John Area);
Ephesus II: Artemission area;
Ephesus III: Port of St. Paul: base of Mount Koressos;
Ephesus IV: north of Aya Suluk;
Ephesus V: Selcuk area.
Because of the man-made harbor structure and the flow of the river, a backwash flow caused the harbor to frequently silt up (by 449 BCE we already read of problems documented about the silting. Later, Eusebius records that Ephesus honoured Emperor Hadrian for dredging and making navigable the harbor). When cleared, Ephesus was in a location that justified a great seaport. The city sat at the convergence of three land routes with a shipping lane from the north via the channel created by the Island of Chios and an opening facing the cities of Macedonia.
The land routes that converged on Ephesus included:
1) The Colossae / Laodicea road (traveling east),
2) The road to Sardis and Galatia (northeast), and
3) The Smyrna (north) main road.
Some scholars estimate the number of people living at Ephesus to have exceeded 250,000 inhabitants during Ephesus III, which would make it perhaps the fourth largest of its day behind:
2) Alexandria; and
3)An Antioch. This large a city was an economic stronghold in Asia Minor, and justified the title supreme metropolis of Asia though there is an evidence that its overall economic standing may have been slowly declining.