The Commercial (Lower) Agora of Ephesus was linked to the harbour by the Arcadiane, and stood close to its junction with the Marble Street, just to the south-west of the theatre. With an almost square plan, the Tetragonos Agora - whose ancient name, meaning the Square Market, has been confirmed by the inscriptions - was built for commercial purposes. It had impressive dimensions as its sides were 111 meters long. The Commercial Agora had three main gates, enabling access from the north onto Harbour Street, the south-east, and the west. The most impressive and best-preserved of these gates is the so-called Gate of Mazaeus and Mithridates on the south-eastern side, very close to the Celsus Library.
This trade area was established in Ephesus in the Hellenistic times, in the 3rd century BCE, as evidenced by the western gate fragments in the Ionic order. Its location was carefully selected, close to the harbour, over a spacious area. As the land was not completely flat there, the ground must have been levelled when it was constructed.
However, the place where the agora was created had been in use for a much longer time. Interestingly, the excavations carried out since 1987 on the western side of the Commercial Agora brought to light the evidence of an early settlement, belonging to Archaic Ephesus, now lying six metres below the ground. The archaeologists hypothesize that these could be the traces of the Smyrna quarter of the city, mentioned by Strabo: "[...] for the Ephesians were fellow-inhabitants of the Smyrnaeans in ancient times, when Ephesus was also called Smyrna. [...] Smyrna was an Amazon who took possession of Ephesus; and hence the name both of the inhabitants and of the city".
The archaeologists revealed five successive building phases, reaching back to the 8th century BCE. These buildings were erected on stone foundations with clay walls, evolving from single-room structures, into large residential houses. They were abandoned by the mid-6th century BCE, possibly because of the rising sea level. In the 6th century BCE, a pottery kiln was erected within these ruined residences. The industrial activities in the western part of the agora continued until the early 4th century BCE. On the opposite, eastern side of the agora, the excavations revealed a graveyard from the period of 6th to 4th centuries BCE.
The Commercial Agora was surrounded by colonnaded porticoes, significantly enhanced during the Roman times. The agora was restructured many times, for the first time in the 1st century BCE, when it got its square shape. The Hellenistic Agora, excavated in 1977, was three meters lower than the current ground level. The archaeologists found a warehouse from the 3rd century BCE in the southwestern corner, a stoa behind it, and the colonnades near the western gate.
The modifications to the plan of the agora were introduced during the reign of Emperor Augustus. By that time, the stoas surrounding the agora had two floors, as indicated by the remains of the staircases discovered in several places. Behind the colonnades, there were around 100 rooms that mainly served as shops but were also used as workshops, warehouses, and meeting places for guild associations. The colonnades surrounding the Agora on four sides were decorated with hundreds of statues of orators, philosophers, athletes, and officials. Only their foundations have been preserved, including the inscriptions that provide valuable information about the social life in Ephesus. The Augustan agora was severely damaged by an earthquake around 23 CE. It was quickly reconstructed and was in operation 20 years later when the statue of Emperor Claudius was sponsored by the Roman merchants.
Not all merchants and artisans who used to work in the Commercial Agora remain anonymous. Possibly the most famous of them is St. Paul who worked there with Priscilla and Aquila in their tentmaking and leatherworking business. Their history is mentioned in the Acts: "There [in Corinth] he met a Jew named Aquila, a native of Pontus, who had recently come from Italy with his wife Priscilla, because Claudius had ordered all Jews to leave Rome. [...] and because he was a tentmaker as they were, he stayed and worked with them." It must have been a lucrative enterprise as the Romans used leather products widely -- from the clothing such as heavy raincoats worn by the soldiers, through harnesses and shields, to footwear. Asia Minor was one of the chief sources of leather for the Romans who needed enormous quantities of this material.
St. Paul also got in trouble there as he criticised the local silversmiths who sold the shrines of Artemis. St. Paul denounced their activity as idolatry and, as a result, was forced to leave the city hastily. The closeness of the Commercial Agora to the harbour may have even been the reason why St. Paul avoided visiting Ephesus on the way to Jerusalem, as described in the Acts 20:16: "Paul had decided to sail past Ephesus to avoid spending time in the province of Asia, for he was in a hurry to reach Jerusalem, if possible, by the day of Pentecost."
During the reign of Emperor Nero, a two-storied double Doric basilica, 150 meters long, was added on the eastern side of the Commercial Agora, along the Marble Street. It was originally intended as a justice court. It is now known as the Hall of Nero, because of the inscription that dedicated this building to Artemis, Nero, his mother Agrippina, and the Ephesians. The basilica was later modified, and its front, facing Marble Street, was closed off, leaving only a small entrance on the northern side.
Extensive restorations of the Commercial Agora were carried out in the times of Emperor Caracalla, at the beginning of the 3rd century when new two-aisled stoas were erected. The agora was damaged by an earthquake again, in the late 4th century CE, and then it was repaired during the reign of Emperor Theodosius I. In this restoration, all the main structural elements of the square were repaired, utilizing the architectural pieces collected throughout Ephesus. In the 6th century CE, the northern stoa of the agora was rebuilt as a massive retaining wall, supporting the artificial hill behind it. The agora remained in use until as late as the 7th century CE, keeping its general plan. However, it lost its original function and was used as a space for workshops, such a glass-makers.
So-called horologion, a combination of solar and water clock, stood at the centre of the Agora. In its original sense, an horologion from the Greek word meaning "the hour-teller" was any device for keeping time, such as a sundial or the Tower of the Winds in Athens that was also a combination of sundials and a water clock. In the case of the horologion of Ephesus, it was discovered as the foundations of the building, measuring some 10 to 6 meters. The archaeologists assumed that it belonged to the horologion on the basis of late Hellenistic inscriptions. However, later studies demonstrated that this structure was from a much later period of the 6th century CE.
This text is a fragment of a guidebook to Ephesus: "The Secrets of Ephesus".